1 <!DOCTYPE article PUBLIC "-//OASIS//DTD DocBook V3.1//EN"[
2 <!entity % dummy "IGNORE">
3 <!entity supported SYSTEM "supported.sgml">
4 <!entity newfeatures SYSTEM "newfeatures.sgml">
5 <!entity p-intro SYSTEM "privoxy.sgml">
6 <!entity seealso SYSTEM "seealso.sgml">
7 <!entity contacting SYSTEM "contacting.sgml">
8 <!entity history SYSTEM "history.sgml">
9 <!entity copyright SYSTEM "copyright.sgml">
10 <!entity license SYSTEM "license.sgml">
11 <!entity p-version "3.0.7">
12 <!entity p-status "stable">
13 <!entity % p-not-stable "IGNORE">
14 <!entity % p-stable "INCLUDE">
15 <!entity % p-text "IGNORE"> <!-- define we are not a text only doc -->
16 <!entity % p-doc "INCLUDE"> <!-- and we are a formal doc -->
17 <!entity % p-supp-userman "INCLUDE"> <!-- Include all from supported.sgml -->
18 <!entity my-copy "©"> <!-- kludge for docbook2man -->
19 <!entity % p-newstuff "INCLUDE"> <!-- exclude stuff from devel versions -->
20 <!entity my-app "<application>Privoxy</application>">
23 File : $Source: /cvsroot/ijbswa/current/doc/source/faq.sgml,v $
26 This file belongs into
27 ijbswa.sourceforge.net:/home/groups/i/ij/ijbswa/htdocs/
29 $Id: faq.sgml,v 2.26 2007/08/05 15:37:55 fabiankeil Exp $
31 Copyright (C) 2001-2007 Privoxy Developers http://privoxy.org
34 Based partially on the Internet Junkbuster FAQ originally written by and
35 Copyright (C) 1997 Anonymous Coders and Junkbusters Corporation.
36 http://www.junkbusters.com/
38 <Qandaset defaultlabel='qanda'>
53 ========================================================================
54 NOTE: Please read developer-manual/documentation.html before touching
57 Please we keep the info in this file as version independent as possible
58 so we only have to maintain one FAQ. Where significant changes are
59 made to Privoxy configuration, please note the change in such a way that
60 it makes sense to both users of older and newer versions.
61 ========================================================================
67 <article id="index" class="faq">
69 <title>Privoxy Frequently Asked Questions</title>
73 <!-- Completely the wrong markup, but very little is allowed -->
74 <!-- in this part of an article. FIXME -->
75 <link linkend="copyright">Copyright</link> &my-copy; 2001-2007 by
76 <ulink url="http://www.privoxy.org/">Privoxy Developers</ulink>
80 <pubdate>$Id: faq.sgml,v 2.26 2007/08/05 15:37:55 fabiankeil Exp $</pubdate>
84 Note: this should generate a separate page, and a live link to it.
85 But it doesn't for some mysterious reason. Please leave commented
86 unless it can be fixed proper. For the time being, the copyright
87 statement will be in copyright.smgl.
91 <legalnotice id="legalnotice">
93 text goes here ........
103 <orgname>By: Privoxy Developers</orgname>
112 This is here to keep vim syntax file from breaking :/
113 If I knew enough to fix it, I would.
114 PLEASE DO NOT REMOVE! HB: hal@foobox.net
119 This FAQ gives quick answers to frequently asked questions about
120 <ulink url="http://www.privoxy.org/">Privoxy</ulink>.
121 It is not a substitute for the
122 <ulink url="../user-manual/index.html"><citetitle>Privoxy User Manual</citetitle></ulink>.
124 This works, at least in some situtations:
125 Test: <ulink url="privoxy-user-manual.pdf"><citetitle>User Manual</citetitle></ulink>.
129 <!-- Include privoxy.sgml boilerplate: -->
130 <para>What is Privoxy?</para> &p-intro;
131 <!-- end boilerplate -->
134 Please note that this document is a work in progress. This copy represents
135 the state at the release of version &p-version;.
136 You can find the latest version of the document at <ulink
137 url="http://www.privoxy.org/faq/">http://www.privoxy.org/faq/</ulink>.
138 Please see the <link linkend="contact">Contact section</link> if you want to
139 contact the developers.
143 <!-- Feel free to send a note to the developers at <email>ijbswa-developers@lists.sourceforge.net</email>. -->
149 <!-- ~~~~~ New section ~~~~~ -->
151 <sect1 id="general"><title>General Information</title>
152 <sect2 renderas="sect3" id="who_uses"><title>Who should use Privoxy?</title>
154 Anyone that is interested in security, privacy, or in
155 finer-grained control over their web and Internet experience.
156 Everyone is encouraged to try &my-app;.
160 <sect2 renderas="sect3" id="bestchoice"><title>Is Privoxy the best choice for
163 &my-app; is certainly a good choice, especially for those who want more
164 control and security. Those that have the ability to fine-tune their installation
165 will benefit the most. One of <application>Privoxy's</application>
166 strength's is that it is highly configurable giving you the ability to
167 completely personalize your installation. Being familiar with, or at least
168 having an interest in learning about <ulink
169 url="http://en.wikipedia.org/wiki/Http">HTTP</ulink> and other networking
170 protocols, <ulink url="http://en.wikipedia.org/wiki/Html">HTML</ulink>,
171 <ulink url="http://en.wikipedia.org/wiki/Internet_Protocol">IP (Internet
172 Protocol)</ulink>, and
173 <ulink url="http://en.wikipedia.org/wiki/Regular_expressions"><quote>Regular
174 Expressions</quote></ulink>
175 will be a big plus and will help you get the most out of &my-app;.
176 A new installation just includes a very basic configuration. The user
177 should take this as a starting point only, and enhance it as he or she
178 sees fit. In fact, the user is encouraged, and expected to, fine-tune the
182 Much of <application>Privoxy's</application> configuration can be done
183 with a <ulink url="http://en.wikipedia.org/wiki/Web_browser">Web browser</ulink>.
184 But there are areas where configuration is done using a
185 <ulink url="http://en.wikipedia.org/wiki/Text_editors">text editor</ulink>
186 to edit configuration files.
190 <sect2 renderas="sect3" id="proxymoron"><title>What is a <quote>proxy</quote>? How does
191 Privoxy work? </title>
193 A <ulink url="http://en.wikipedia.org/wiki/Proxy_server">web proxy</ulink>
194 is a service, based on a software such as
195 <application>Privoxy</application>, that clients (i.e. browsers) can use
196 instead of connecting directly to web servers on the Internet. The
197 clients then ask the proxy to fetch the objects they need (web pages,
198 images, movies etc) on their behalf, and when the proxy has done so, it
199 hands the results back to the client. It is a <quote>go-between</quote>. See
200 the <ulink url="http://en.wikipedia.org/wiki/Proxy_server">Wikipedia proxy
201 definition</ulink> for more.
204 There are many reasons to use web proxies, such as security (firewalling),
205 efficiency (caching) and others, and there are any number of proxies
206 to accommodate those needs.
209 <application>Privoxy</application> is a proxy that is primarily focused on privacy
210 protection, ad and junk elimination and freeing the user from restrictions placed on his
211 activities. Sitting between your browser(s) and the Internet,
212 it is in a perfect position to filter outbound personal information that your
213 browser is leaking, as well as inbound junk. It uses a variety of techniques to do
214 this, all of which are under your complete control via the various configuration
215 files and options. Being a proxy also makes it easier to share
216 configurations among multiple browsers and/or users.
220 <sect2 renderas="sect3" id="otherstuff">
221 <title>Does Privoxy do anything more than ad blocking?</title>
223 Yes, ad blocking is but one possible use. There are many, many ways &my-app;
224 can be used to sanitize and customize web browsing.
228 <sect2 renderas="sect3" id="newjb"><title>What is this new version of
229 <quote><citetitle>Junkbuster</citetitle></quote>?</title>
231 <!-- Include history.sgml -->
238 <sect2 renderas="sect3">
239 <title id="whyprivoxy">Why <quote>Privoxy</quote>? Why change the name from
240 Junkbuster at all?</title>
242 Though outdated, <ulink url="http://junkbusters.com/">Junkbusters Corporation</ulink>
243 continues to offer their original version of the <application>Internet
244 Junkbuster</application>, so publishing our
245 <application> Junkbuster</application>-derived software under the same name
249 There are also potential legal complications from our use of the
250 <application>Junkbuster</application> name, which is a registered trademark of
251 <ulink url="http://junkbusters.com/">Junkbusters Corporation</ulink>.
252 There are, however, no objections from Junkbusters Corporation to the
253 <application>Privoxy</application> project itself, and they, in fact, still
254 share our ideals and goals.
257 The developers also believed that there are so many improvements over the original
258 code, that it was time to make a clean break from the past and make
259 a name in their own right.
262 <application>Privoxy</application> is the
263 <quote><emphasis>Privacy Enhancing Proxy</emphasis></quote>. Also, its content
264 modification and junk suppression gives <emphasis>you</emphasis>, the user, more
265 control, more freedom, and allows you to browse your personal and
266 <quote><emphasis>private</emphasis> edition</quote> of the web.
270 <sect2 renderas="sect3" id="differs"><title>How does Privoxy differ
271 from the old Junkbuster?</title>
273 <application>Privoxy</application> picks up where
274 <application>Junkbuster</application> left off. All the old features remain.
275 The new <application>Privoxy</application> still blocks ads and banners,
277 url="http://en.wikipedia.org/wiki/Browser_cookie">cookies</ulink>, and still
278 helps protect your privacy. But, these are all greatly enhanced, and many,
279 many new features have been added, all in the same vein.
282 The configuration has changed significantly as well. This is something that
283 users will notice right off the bat if upgrading from
284 <application>Junkbuster</application> 2.0.x. The <quote>blocklist</quote>
285 <quote>cookielist</quote>, <quote>imagelist</quote> and much more has been
286 combined into the <quote>actions</quote> files, with a completely different
287 syntax. <![%p-newstuff;[ See the <ulink url="../user-manual/whatsnew.html">What's New</ulink>
288 page for the latest updates.]]>
291 <application>Privoxy</application>'s new features include:
294 <!-- Include newfeatures.sgml: -->
300 <sect2 renderas="sect3" id="whatsanad">
301 <title id="knows">How does Privoxy know what is
302 an ad, and what is not?</title>
304 <application>Privoxy</application>'s approach to blocking ads is twofold:
307 First, there are certain patterns in the <emphasis>locations</emphasis> (URLs)
308 of banner images. This applies to both the path (you wouldn't guess how many
309 web sites serve their banners from a directory called <quote>banners</quote>!)
310 and the host (blocking the big banner hosting services like doublecklick.net
311 already helps a lot). <application>Privoxy</application> takes advantage of this
312 fact by using <ulink url="../user-manual/actions-file.html#AF-PATTERNS">URL
313 patterns</ulink> to sort out and block the requests for things that sound
314 like they would be ads or banners.
317 Second, banners tend to come in certain <emphasis>sizes</emphasis>. But you
318 can't tell the size of an image by its URL without downloading it, and if you
319 do, it's too late to save bandwidth. Therefore, <application>Privoxy</application>
320 also inspects the HTML sources of web pages while they are loaded, and replaces
321 references to images with standard banner sizes by dummy references, so that
322 your browser doesn't request them anymore in the first place.
325 Both of this involves a certain amount of guesswork and is, of course, freely
326 and readily configurable.
330 <sect2 renderas="sect3">
331 <title id="mistakes">Can Privoxy make mistakes?
332 This does not sound very scientific.</title>
334 Actually, it's a black art ;-) And yes, it is always possible to have a broad
335 rule accidentally block or change something by mistake. You will almost surely
336 run into such situations at some point. It is tricky writing rules to
337 cover every conceivable possibility, and not occasionally get false positives.
341 But this should not be a big concern since the
342 <application>Privoxy</application> configuration is very flexible, and
343 includes tools to help identify these types of situations so they can be
344 addressed as needed, allowing you to customize your installation.
345 (<link linkend="badsite">See the Troubleshooting section below</link>.)
350 <sect2 renderas="sect3">
351 <title id="configornot">Will I have to configure Privoxy
352 before I can use it?</title>
354 No, not really. The default installation should give you a good starting
355 point, and block <emphasis>most</emphasis> ads and unwanted content. Many of
356 the more advanced features are off by default, and would require you to
360 You do have to set up your browser to use
361 <application>Privoxy</application> (see the <link
362 linkend="firststep">Installation section below</link>).
365 And you will certainly run into situations where there are false positives,
366 or ads not being blocked that you may not want to see. In these cases, you
367 would certainly benefit by customizing <application>Privoxy's</application>
368 configuration to more closely match your individual situation. And we would
369 encourage you to do this. This is where the real power of
370 <application>Privoxy</application> lies!
375 <sect2 renderas="sect3" id="lan">
376 <title>Can Privoxy run as a server on a network?</title>
378 Yes, &my-app; runs as a server already, and can easily be configured to
379 <quote>serve</quote> more than one client. See <link linkend="lanconfig">
380 How can I set up Privoxy to act as a proxy for my LAN</link> below.
384 <sect2 renderas="sect3" id="browsers2"><title>My browser does the same things as
385 Privoxy. Why should I use Privoxy at all?</title>
387 Modern browsers do indeed have <emphasis>some</emphasis> of the same
388 functionality as <application>Privoxy</application>. Maybe this is
389 adequate for you. But <application>Privoxy</application> is much more
390 versatile and powerful, and can do a number of things that browsers just can't.
393 In addition, a proxy is good choice if you use multiple browsers, or
394 have a LAN with multiple computers since &my-app; can run as a server
395 application. This way all the configuration is in one place, and you don't
396 have to maintain a similar configuration for possibly many browsers or
401 <sect2 renderas="sect3" id="whytrust"><title>Why should I trust Privoxy?</title>
403 The most important reason is because you have access to
404 <emphasis>everything</emphasis>, and you can control everything. You can
405 check every line of every configuration file yourself. You can check every
406 last bit of source code should you desire. And even if you can't read code,
407 there should be some comfort in knowing that thousands of other people can,
408 and some of them do read it. You can build the software from scratch, if you want,
409 so that you know the executable is clean, and that it is
410 <emphasis>yours</emphasis>. In fact, we encourage this level of scrutiny. It
411 is one reason we use &my-app; ourselves.
415 <sect2 renderas="sect3" id="license"><title>Is there is a license or fee? What about a
416 warranty? Registration?</title>
418 <application>Privoxy</application> is licensed under the <ulink
419 url="http://www.gnu.org/licenses/old-licenses/gpl-2.0.html">GNU General Public License (GPL) version 2</ulink>.
420 It is free to use, copy, modify or distribute as you wish under the terms of this
421 license. Please see the <link linkend="copyright">Copyright</link> section for more
422 information on the license and copyright. Or the <filename>LICENSE</filename> file
423 that should be included.
426 There is <emphasis>no warranty</emphasis> of any kind, expressed, implied or otherwise.
427 That is something that would cost real money ;-) There is no registration either.
428 <application>Privoxy</application> really is <emphasis>free</emphasis>
434 <sect2 renderas="sect3" id="spyware">
435 <title>Can Privoxy remove spyware? Adware? Viruses?</title>
437 No, at least not reliable enough to trust it. &my-app; is not designed to be
438 a malware removal tool and the default configuration doesn't even try to
439 filter out any malware.
442 &my-app; could help prevent contact from (known) sites that use such
443 tactics with appropriate configuration rules, and thus could conceivably
444 prevent contamination from such sites.
449 <sect2 renderas="sect3" id="otherads">
450 <title>Can I use Privoxy with other ad-blocking software?</title>
452 &my-app; should work fine with other proxies and other software in general.
455 But it is probably not necessary to use &my-app; in conjunction with other
456 ad-blocking products, and this could conceivably cause undesirable results.
457 It would be better to choose one software or the other and work a little to
458 tweak its configuration to your liking.
462 <sect2 renderas="sect3" id="jointeam"><title>I would like to help you, what can I do?</title>
464 <sect3 renderas="sect4" id="jointeam-work"><title>Would you like to participate?</title>
466 Well, we <emphasis>always</emphasis> need help. There is something for
467 everybody who wants to help us. We welcome new developers, packagers,
468 testers, documentation writers or really anyone with a desire to help in
469 any way. You <emphasis>DO NOT</emphasis> need to be a
470 <quote>programmer</quote>. There are many other tasks available. In fact,
471 the programmers often can't spend as much time programming because of some
472 of the other, more mundane things that need to be done, like checking the
473 Tracker feedback sections.
476 So first thing, <ulink
477 url="https://sourceforge.net/account/register.php">get an account on SourceForge.net</ulink>
478 and mail your id to the <ulink url="mailto:ijbswa-developers@lists.sourceforge.net">developers
479 mailing list</ulink>. Then, please read the <ulink
480 url="../developer-manual/index.html">Developer's Manual</ulink>, at least
481 the pertinent sections.
485 <sect3 renderas="sect4" id="jointeam-money"><title>Contribute!</title>
487 We, of course, welcome donations and could use money for domain registering,
488 buying software to test <application>Privoxy</application> with, and, of course,
489 for regular world-wide get-togethers (hahaha). If you enjoy the software and feel
490 like helping us with a donation, just <ulink
491 url="mailto: ijbswa-developers@lists.sourceforge.net">drop us a note</ulink>.
495 <sect3 renderas="sect4" id="jointeam-software"><title>Software</title>
497 If you are a vendor of a web-related software like a browser, web server
498 or proxy, and would like us to ensure that <application>Privoxy</application>
499 runs smoothly with your product, you might consider supplying us with a
500 copy or license. We can't, however, guarantee that we will fix all potential
501 compatibility issues as a result.
511 <!-- ~~~~~ New section ~~~~~ -->
513 <sect1 id="installation"><title>Installation</title>
515 <sect2 renderas="sect3" id="whichbrowsers">
516 <title>Which browsers are supported by Privoxy?</title>
518 Any browser that can be configured to use a proxy, which
519 should be virtually all browsers, including
520 <application>Firefox</application>, <application>Internet
521 Explorer</application>, and <application>Opera</application> among others.
522 Direct browser support is not an absolute requirement since
523 <application>Privoxy</application> runs as a separate application and talks
524 to the browser in the standardized HTTP protocol, just like a web server
529 <sect2 renderas="sect3" id="whichos">
530 <title>Which operating systems are supported?</title>
532 Include supported.sgml here:
537 <sect2 renderas="sect3" id="email-client">
538 <title>Can I use Privoxy with my email client?</title>
540 As long as there is some way to set a HTTP proxy for the client, then yes,
541 any application can be used, whether it is strictly speaking a
542 <quote>browser</quote> or not. Though this may not be the best approach for
543 dealing with some of the common abuses of HTML in email. See <link
544 linkend="outlook">How can I configure <application>Privoxy</application>
545 with <application>Outlook Express</application>?</link> below for more on
549 Be aware that HTML email presents a number of unique security and privacy
550 related issues, that can require advanced skills to overcome. The developers
551 recommend using email clients that can be configured to convert HTML to plain
552 text for these reasons.
556 <sect2 renderas="sect3" id="newinstall"><title>Can I install
557 Privoxy over Junkbuster?</title>
559 We recommend you un-install <application>Junkbuster</application>
560 first to minimize conflicts and confusion. You may want to
561 save your old configuration files for future reference. The configuration
562 files and syntax have substantially changed, so you will need to manually
563 port your old patterns. See the <ulink url="../user-manual/upgradersnote.html">note
564 to upgraders</ulink> and <ulink url="../user-manual/installation.html">installation
565 chapter</ulink> in the <ulink url="../user-manual/index.html">User Manual</ulink>
569 Note: Some installers may automatically un-install
570 <application>Junkbuster</application>, if present!
575 <sect2 renderas="sect3" id="firststep">
576 <title>I just installed Privoxy. Is there anything
577 special I have to do now?</title>
580 All browsers must be told to use <application>Privoxy</application>
581 as a proxy by specifying the correct proxy address and port number
582 in the appropriate configuration area for the browser. See
583 <ulink url="../user-manual/startup.html">the User Manual for more
584 details</ulink>. You should also flush your browser's memory and disk cache to get rid of any
585 cached junk items, and remove any stored
586 <ulink url="http://en.wikipedia.org/wiki/Browser_cookie">cookies</ulink>.
593 <sect2 renderas="sect3" id="localhost"><title>What is the proxy address of Privoxy?</title>
595 If you set up the <application>Privoxy</application> to run on
596 the computer you browse from (rather than your ISP's server or some
597 networked computer on a LAN), the proxy will be on <literal>127.0.0.1</literal>
598 (sometimes referred to as <quote>localhost</quote>,
599 which is the special name used by every computer on the Internet to refer
600 to itself) and the port will be 8118 (unless you have <application>Privoxy</application>
601 to run on a different port with the <ulink
602 url="../user-manual/config.html#LISTEN-ADDRESS">listen-address</ulink> config option).
605 When configuring your browser's proxy settings you typically enter
606 the word <quote>localhost</quote> or the IP address <quote>127.0.0.1</quote>
607 in the boxes next to <quote>HTTP</quote> and <quote>Secure</quote> (HTTPS) and
608 then the number <quote>8118</quote> for <quote>port</quote>.
609 This tells your browser to send all web requests to <application>Privoxy</application>
610 instead of directly to the Internet.
613 <application>Privoxy</application> can also be used to proxy for
614 a Local Area Network. In this case, your would enter either the IP
615 address of the LAN host where <application>Privoxy</application>
616 is running, or the equivalent hostname, e.g. <literal>192.168.1.1</literal>.
617 Port assignment would be same as above. Note that
618 <application>Privoxy</application> doesn't listen on any LAN interfaces by
622 <application>Privoxy</application> does not currently handle
623 any other protocols such as FTP, SMTP, IM, IRC, ICQ, etc. Be sure that
624 proxying any of these other protocols is not activated.
628 <sect2 renderas="sect3" id="nothing">
629 <title>I just installed Privoxy, and nothing is happening.
630 All the ads are there. What's wrong?</title>
633 Did you configure your browser to use <application>Privoxy</application>
634 as a proxy? It does not sound like it. See above. You might also try flushing
635 the browser's caches to force a full re-reading of pages. You can verify
636 that <application>Privoxy</application> is running, and your browser
637 is correctly configured by entering the special URL:
638 <ulink url="http://p.p/">http://p.p/</ulink>.
639 <!-- Use http://p.p/ instead of http://config.privoxy.org/ here because
640 of potential redirect caching problem (see next Q). -->
641 This should take you to a page titled <quote>This is Privoxy..</quote> with
642 access to <application>Privoxy's</application> internal configuration.
643 If you see this, then you are good to go. If you receive a page saying
644 <quote>Privoxy is not running</quote>, then the browser is not set up to use
645 your <application>Privoxy</application> installation.
646 If you receive anything else (probably nothing at all), it could either
647 be that the browser is not set up correctly, or that
648 <application>Privoxy</application> is not running at all. Check the <ulink
649 url="../user-manual/config.html#LOGFILE">log file</ulink>. For instructions
650 on starting <application>Privoxy</application> and browser configuration,
651 see the <ulink url="http://www.privoxy.org/user-manual/startup.html">chapter
652 on starting <application>Privoxy</application></ulink> in the
653 <ulink url="http://www.privoxy.org/user-manual/">User Manual</ulink>.
658 <sect2 renderas="sect3" id="notused">
659 <title>I get a <quote>Privoxy is not being used</quote> dummy page although
660 Privoxy is running and being used.</title>
663 First, make sure that Privoxy is <emphasis>really</emphasis> running and
664 being used by visiting <ulink url="http://p.p/">http://p.p/</ulink>. You
665 should see the <application>Privoxy</application> main page. If not, see
666 the <ulink url="http://www.privoxy.org/user-manual/startup.html">chapter
667 on starting <application>Privoxy</application></ulink> in the
668 <ulink url="http://www.privoxy.org/user-manual/">User Manual</ulink>.
672 Now if <ulink url="http://p.p/">http://p.p/</ulink> works for you, but
673 other parts of <application>Privoxy</application>'s web interface show
674 the dummy page, your browser has cached a redirection it encountered before
675 <application>Privoxy</application> was being used. You need to clear your
676 browser's cache. Note that shift-reloading the dummy page won't help, since
677 that'll only refresh the dummy page, not the redirection that lead you there.
681 The procedure for clearing the cache varies from browser to browser. For
682 example, <application>Mozilla/Netscape</application> users would click
683 <guibutton>Edit</guibutton> --> <guibutton>Preferences</guibutton> -->
684 <guibutton>Advanced</guibutton> --> <guibutton>Cache</guibutton> and
685 then click both <quote><guibutton>Clear Memory Cache</guibutton></quote>
686 and <quote><guibutton>Clear Disk Cache</guibutton></quote>.
687 And, <application>Firefox</application> users would click
688 <guibutton>Tools</guibutton> --> <guibutton>Options</guibutton> -->
689 <guibutton>Privacy</guibutton> --> <guibutton>Cache</guibutton> and
690 then click <quote><guibutton>Clear Cache Now</guibutton></quote>.
698 <!-- ~~~~~ New section ~~~~~ -->
700 <sect1 id="configuration"><title>Configuration</title>
701 <sect2 renderas="sect3">
702 <title id="actionsfile">What exactly is an <quote>actions</quote> file?</title>
705 &my-app; utilizes the concept of <quote>
706 <ulink url="../user-manual/actions-file.html#ACTIONS">actions</ulink></quote>
707 that are used to manipulate and control web page data.
708 <ulink url="../user-manual/actions-file.html">Actions files</ulink>
709 are where these <ulink url="../user-manual/actions-file.html#ACTIONS">actions</ulink>
710 that <application>Privoxy</application> could take while processing a certain
711 request, are configured. Typically, you would define a set of default actions
712 that apply globally to all URLs, then add exceptions to these defaults where needed.
713 There is a wide array of actions available that give the user a high degree
714 of control and flexibility on how to process each and every web page.
718 Actions can be defined on a <ulink
719 url="../user-manual/actions-file.html#AF-PATTERNS">URL pattern</ulink> basis, i.e.
720 for single URLs, whole web sites, groups or parts thereof etc. Actions can also be
721 grouped together and then applied to requests matching one or more patterns.
722 There are many possible actions that might apply to any given site. As an example,
723 if you are blocking <ulink url="http://en.wikipedia.org/wiki/Browser_cookie">cookies</ulink>
724 as one of your default actions, but need to accept cookies from a given site,
725 you would need to define an exception for this site in one of your actions
726 files, preferably in <filename>user.action</filename>.
731 <sect2 renderas="sect3" id="actionss">
732 <title>The <quote>actions</quote> concept confuses me. Please list
733 some of these <quote>actions</quote>.</title>
735 For a comprehensive discussion of the actions concept, please refer
736 to the <ulink url="../user-manual/actions-file.html">actions file
737 chapter</ulink> in the <ulink url="../user-manual/index.html">User
738 Manual</ulink>. It includes a <ulink
739 url="../user-manual/actions-file.html#ACTIONS">list of all actions</ulink>
740 and an <ulink url="../user-manual/actions-file.html#ACT-EXAMPLES">actions
741 file tutorial</ulink> to get you started.
746 <sect2 renderas="sect3">
747 <title id="actconfig">How are actions files configured? What is the easiest
748 way to do this?</title>
751 Actions files are just text files in a special syntax and can be edited
752 with a text editor. But probably the easiest way is to access
753 <application>Privoxy</application>'s user interface with your web browser
754 at <ulink url="http://config.privoxy.org/">http://config.privoxy.org/</ulink>
755 (Shortcut: <ulink url="http://p.p/">http://p.p/</ulink>) and then select
756 <quote><ulink url="http://config.privoxy.org/show-status">View &
757 change the current configuration</ulink></quote> from the menu.
762 <sect2 renderas="sect3">
763 <title>There are several different <quote>actions</quote> files. What are
764 the differences?</title>
767 are being included by the developers, to be used for
768 different purposes: These are
769 <filename>default.action</filename>, the <quote>main</quote> actions file
770 which is actively maintained by the <application>Privoxy</application>
771 developers and typically sets the default policies, <filename>user.action</filename>, where users are encouraged
772 to make their private customizations, and <filename>standard.action</filename>,
773 which is for internal <application>Privoxy</application> use only.
774 Please see <ulink url="../user-manual/actions-file.html">the actions chapter</ulink>
775 in the <ulink url="../user-manual/index.html">User Manual</ulink> for a more
776 detailed explanation.
780 Earlier versions included three different versions of the
781 <filename>default.action</filename> file. The new scheme allows for
782 greater flexibility of local configuration, and for browser based
783 selection of pre-defined <quote>aggressiveness</quote> levels.
788 <sect2 renderas="sect3" id="getupdates"><title>Where can I get updated Actions Files?</title>
790 Based on your feedback and the continuing development, updates of
791 <filename>default.action</filename> will be
792 made available from time to time on the <ulink
793 url="http://sourceforge.net/project/showfiles.php?group_id=11118">files section</ulink> of
794 our <ulink url="http://sf.net/projects/ijbswa/">project page</ulink>.
798 If you wish to receive an email notification whenever we release updates of
799 <application>Privoxy</application> or the actions file, <ulink
800 url="http://lists.sourceforge.net/lists/listinfo/ijbswa-announce/">subscribe
801 to our announce mailing list</ulink>, ijbswa-announce@lists.sourceforge.net.
806 <sect2 renderas="sect3" id="newconfig"><title>Can I use my old config files?</title>
808 The syntax and purpose of configuration files has remained roughly the
809 same throughout the 3.x series, but backwards compatibility is not guaranteed.
810 Also each release contains updated, <quote>improved</quote> versions and it is
811 therefore recommended to use the newer configuration files.
813 If upgrading from version prior to 3.0.4 the syntax for <literal>fast-redirects</literal>
814 has changed. See the <ulink url="../user-manual/whatsnew.html">What's New section</ulink>
815 of the <citetitle>User Manual</citetitle> for details.]]>
818 But all configuration files have substantially
819 changed from the <application>Junkbuster</application> days, and early
820 versions of <application>Privoxy 2.x</application>. The old files, like
821 <filename>blocklist</filename> will not work at all.
823 <![%p-newstuff;[ <para>
824 Refer to the <ulink url="../user-manual/whatsnew.html">What's New</ulink>
825 page for information on configuration changes that may occur from one release to another.
829 <sect2 renderas="sect3" id="difficult">
830 <title>Why is the configuration so complicated?</title>
832 <quote>Complicated</quote> is in the eye of the beholder. Those that are
833 familiar with some of the underlying concepts, such as regular expression
834 syntax, take to it like a fish takes to water. Also, software that tries
835 hard to be <quote>user friendly</quote>, often lacks sophistication and
836 flexibility. There is always that trade-off there between power vs.
837 easy-of-use. Furthermore, anyone is welcome to contribute ideas and
838 implementations to enhance &my-app;.
842 <sect2 renderas="sect3" id="yahoo"><title>How can I make my Yahoo/Hotmail/Gmail account work?</title>
844 The default configuration shouldn't impact the usability of any of these services.
845 It may, however, make all <ulink
846 url="http://en.wikipedia.org/wiki/Browser_cookie">cookies</ulink>
847 temporary, so that your browser will forget your
848 login credentials in between browser sessions. If you would like not to have to log
849 in manually each time you access those websites, simply turn off all cookie handling
850 for them in the <filename>user.action</filename> file. An example for yahoo might
854 <screen># Allow all cookies for Yahoo login:
856 { -<ulink url="../user-manual/actions-file.html#CRUNCH-INCOMING-COOKIES">crunch-incoming-cookies</ulink> -<ulink url="../user-manual/actions-file.html#CRUNCH-OUTGOING-COOKIES">crunch-outgoing-cookies</ulink> -<ulink url="../user-manual/actions-file.html#SESSION-COOKIES-ONLY">session-cookies-only</ulink> }
857 .login.yahoo.com</screen>
860 These kinds of sites are often quite complex and heavy with
861 <ulink url="http://en.wikipedia.org/wiki/Javascript">Javascript</ulink> and
862 thus <quote>fragile</quote>. So if <emphasis>still</emphasis> a problem,
864 url="../user-manual/actions-file.html#ALIASES">alias</ulink> just for such
868 <screen># Gmail is a _fragile_ site:
870 { <literal>fragile</literal> }
872 mail.google.com</screen>
875 Be sure to flush your browser's caches whenever making these kinds of
876 changes, just to make sure the changes <quote>take</quote>.
879 Make sure the domain, host and path are appropriate as well. Your browser can
880 tell you where you are specifically and you should use that information for
881 your configuration settings. Note that above it is not referenced as
882 <literal>gmail.com</literal>, which is a valid domain name.
887 <sect2 renderas="sect3" id="configfiles"> <title>What's the difference between the
888 <quote>Cautious</quote>, <quote>Medium</quote> and <quote>Advanced</quote> defaults?</title>
890 Configuring <application>Privoxy</application> is not entirely trivial. To
891 help you get started, we provide you with three different default action
892 <quote>profiles</quote> in the web based actions file editor at <ulink
893 url="http://config.privoxy.org/show-status">http://config.privoxy.org/show-status</ulink>.
894 See the <ulink url="../user-manual/actions-file.html"><citetitle>User
895 Manual</citetitle></ulink> for a list of actions, and how the default
900 Where the defaults are likely to break some sites, exceptions for
901 known popular <quote>problem</quote> sites are included, but in
902 general, the more aggressive your default settings are, the more exceptions
903 you will have to make later. New users are best to start off in
904 <quote>Cautious</quote> setting. This is safest and will have the fewest
905 problems. See the <ulink
906 url="../user-manual/index.html"><citetitle>User Manual</citetitle></ulink>
907 for a more detailed discussion.
911 It should be noted that the <quote>Advanced</quote> profile (formerly known
912 as the <quote>Adventuresome</quote> profile) is more
913 aggressive, and will make use of some of
914 <application>Privoxy's</application> advanced features. Use at your own risk!
919 <sect2 renderas="sect3" id="browseconfig"> <title>Why can I change the configuration
920 with a browser? Does that not raise security issues?</title>
922 It may seem strange that regular users can edit the config files with their
923 browsers, although the whole <filename>/etc/privoxy</filename> hierarchy
924 belongs to the user <quote>privoxy</quote>, with only 644 permissions.
927 When you use the browser-based editor, <application>Privoxy</application>
928 itself is writing to the config files. Because
929 <application>Privoxy</application> is running as the user <quote>privoxy</quote>,
930 it can update the config files.
933 If you run <application>Privoxy</application> for multiple untrusted users (e.g. in
934 a LAN), you will probably want to turn the web-based editor and remote toggle
935 features off by setting <quote><literal><ulink
936 url="../user-manual/config.html#ENABLE-EDIT-ACTIONS">enable-edit-actions</ulink>
937 0</literal></quote> and <quote><literal><ulink
938 url="../user-manual/config.html#ENABLE-REMOTE-TOGGLE">enable-remote-toggle</ulink>
939 0</literal></quote> in the <ulink url="../user-manual/config.html">main configuration file</ulink>.
942 Note that in the default configuration, only local users (i.e. those on
943 <quote>localhost</quote>) can connect to <application>Privoxy</application>,
944 so this is (normally) not a security problem.
949 <sect2 renderas="sect3">
950 <title id="filterfile">What is the <filename>default.filter</filename> file? What is a <quote>filter</quote>?</title>
952 The <ulink url="../user-manual/filter-file.html"><filename>default.filter</filename></ulink>
953 file is where <emphasis>filters</emphasis> as supplied by the developers are defined.
954 Filters are a special subset of actions that can be used to modify or
955 remove, web page content on the fly. Filters apply to <emphasis>anything</emphasis>
956 in the page source (and optionally both client and server headers), including
957 HTML tags, and JavaScript. Regular expressions are used to accomplish this.
958 There are a number of pre-defined filters to deal with common annoyances. The
959 filters are only defined here, to invoke them, you need to use the
961 url="../user-manual/actions-file.html#FILTER"><literal>filter</literal>
962 action</ulink> in one of the actions files. Filtering is automatically
963 disabled for inappropriate MIME types.
967 If you are familiar with regular expressions, and HTML, you can look at
968 the provided <filename>default.filter</filename> with a text editor and define
969 your own filters. This is potentially a very powerful feature, but
970 requires some expertise in both regular expressions and HTML/HTTP.
971 <![%p-newstuff;[ You should
972 place any modifications to the default filters, or any new ones you create
973 in a separate file, such as <filename>user.filter</filename>, so they won't
974 be overwritten during upgrades.
975 The ability to define multiple filter files
976 in <filename>config</filename> is a new feature as of v. 3.0.5.]]>
980 There is no GUI editor option for this part of the configuration,
981 but you can disable/enable the various pre-defined filters of the included
982 <filename>default.filter</filename> file with the <ulink
983 url="http://config.privoxy.org/show-status">web-based actions file editor</ulink>.
988 <sect2 renderas="sect3" id="lanconfig">
989 <title>How can I set up Privoxy to act as a proxy for my
992 By default, <application>Privoxy</application> only responds to requests
993 from <literal>127.0.0.1</literal> (localhost). To have it act as a server for
994 a network, this needs to be changed in the <ulink
995 url="../user-manual/config.html">main configuration file</ulink>. Look for
997 url="../user-manual/config.html#LISTEN-ADDRESS">listen-address</ulink></literal>
998 option, which may be commented out with a <quote>#</quote> symbol. Make sure
999 it is uncommented, and assign it the address of the LAN gateway interface,
1000 and port number to use. Assuming your LAN address is 192.168.1.1 and you
1001 wish to run <application>Privoxy</application> on port 8118, this line
1007 listen-address 192.168.1.1:8118</screen>
1011 Save the file, and restart <application>Privoxy</application>. Configure
1012 all browsers on the network then to use this address and port number.
1016 Alternately, you can have <application>Privoxy</application> listen on
1017 all available interfaces:
1022 listen-address :8118</screen>
1026 And then use <application>Privoxy's</application>
1028 url="../user-manual/config.html#PERMIT-ACCESS">permit-access</ulink>
1029 feature to limit connections. A firewall in this situation is recommended
1034 The above steps should be the same for any TCP network, regardless of
1039 If you run <application>Privoxy</application> on a LAN with untrusted users,
1040 we recommend that you double-check the <ulink
1041 url="../user-manual/config.html#ACCESS-CONTROL">access control and security</ulink>
1048 <sect2 renderas="sect3">
1049 <title id="noseeum">Instead of ads, now I get a checkerboard pattern. I don't want to see anything.</title>
1051 The replacement for blocked images can be controlled with the <ulink
1052 url="../user-manual/actions-file.html#SET-IMAGE-BLOCKER"><literal>set-image-blocker</literal>
1053 action</ulink>. You have the choice of a checkerboard pattern, a transparent 1x1 GIF
1054 image (aka <quote>blank</quote>), or a redirect to a custom image of your choice.
1055 Note that this choice only has effect for images which are blocked as images, i.e.
1056 whose URLs match both a <literal><ulink
1057 url="../user-manual/actions-file.html#HANDLE-AS-IMAGE">handle-as-image</ulink></literal>
1058 <emphasis>and</emphasis> <literal><ulink
1059 url="../user-manual/actions-file.html#BLOCK">block</ulink></literal> action.
1062 If you want to see nothing, then change the <ulink
1063 url="../user-manual/actions-file.html#SET-IMAGE-BLOCKER"><literal>set-image-blocker</literal>
1064 action</ulink> to <quote>blank</quote>. This can be done by editing the
1065 <filename>user.action</filename> file, or through the <ulink
1066 url="http://config.privoxy.org/show-status">web-based actions file editor</ulink>.
1071 <sect2 renderas="sect3">
1072 <title id="whyseeum">Why would anybody want to see a checkerboard pattern?</title>
1074 Remember that <link linkend="whatsanad">telling which image is an ad and which
1075 isn't</link>, is an educated guess. While we hope that the standard configuration
1076 is rather smart, it will make occasional mistakes. The checkerboard image is visually
1077 decent, and it shows you where images have been blocked, which can be very
1078 helpful in case some navigation aid or otherwise innocent image was
1079 erroneously blocked. It is recommended for new users so they can
1080 <quote>see</quote> what is happening. Some people might also enjoy seeing how
1081 many banners they <emphasis>don't</emphasis> have to see.
1086 <sect2 renderas="sect3">
1087 <title id="blockedbytext">I see some images being replaced by a text
1088 instead of the checkerboard image. Why and how do I get rid of this?</title>
1090 This happens when the banners are not embedded in the HTML code of the
1091 page itself, but in separate HTML (sub)documents that are loaded into (i)frames
1092 or (i)layers, and these external HTML documents are blocked. Being non-images
1093 they get replaced by a substitute HTML page rather than a substitute image,
1094 which wouldn't work out technically, since the browser expects and accepts
1095 only HTML when it has requested an HTML document.
1098 The substitute page adapts to the available space and shows itself as a
1099 miniature two-liner if loaded into small frames, or full-blown with a
1100 large red "BLOCKED" banner if space allows.
1103 If you prefer the banners to be blocked by images, you must see to it that
1104 the HTML documents in which they are embedded are not blocked. Clicking
1105 the <quote>See why</quote> link offered in the substitute page will show
1106 you which rule blocked the page. After changing the rule and un-blocking
1107 the HTML documents, the browser will try to load the actual banner images
1108 and the usual image blocking will (hopefully!) kick in.
1113 <sect2 renderas="sect3" id="srvany">
1114 <title>Can Privoxy run as a service
1115 on Win2K/NT/XP?</title>
1118 Yes. Version 3.0.5 introduces full <application>Windows</application> service
1119 functionality. See <ulink url="../user-manual/installation.html#installation-pack-win">
1120 the <citetitle>User Manual</citetitle></ulink> for details on how to install and configure
1121 <application>Privoxy</application> as a service.
1124 Earlier ]]>3.x versions could run as a system service using <command>srvany.exe</command>.
1125 See the discussion at <ulink
1126 url="http://sourceforge.net/tracker/?func=detail&atid=361118&aid=485617&group_id=11118">http://sourceforge.net/tracker/?func=detail&atid=361118&aid=485617&group_id=11118</ulink>,
1127 for details, and a sample configuration.
1132 <sect2 renderas="sect3" id="otherproxy">
1133 <title>How can I make Privoxy work with other
1134 proxies like Squid or Tor?</title>
1136 This can be done and is often useful to combine the benefits of
1137 <application>Privoxy</application> with those of a another proxy.
1139 url="../user-manual/config.html#FORWARDING">forwarding chapter</ulink>
1140 in the <ulink url="../user-manual/index.html">User Manual</ulink> which
1141 describes how to do this, and the <link linkend="TOR">
1142 How do I use Privoxy together with
1143 Tor</link> section below.
1147 <sect2 renderas="sect3" id="port-80">
1148 <title>Can I just set Privoxy to use port 80
1149 and thus avoid individual browser configuration?</title>
1152 No, its more complicated than that. This only works with special kinds
1153 of proxies known as <quote>intercepting</quote> proxies (see below).
1158 <sect2 renderas="sect3" id="transparent">
1159 <title>Can Privoxy run as a <quote>transparent
1160 </quote> proxy?</title>
1162 The whole idea of Privoxy is to modify client requests
1163 and server responses in all sorts of ways and therefore
1164 it's not a transparent proxy as described in
1165 <ulink url="http://tools.ietf.org/html/rfc2616">RFC 2616</ulink>.
1168 However, some people say <quote>transparent proxy</quote> when they
1169 mean <quote>intercepting proxy</quote>. If you are one of them,
1170 please read the <ulink url="#intercepting">next entry</ulink>.
1175 <sect2 renderas="sect3" id="intercepting">
1176 <title>Can Privoxy run as a <quote>intercepting</quote> proxy?</title>
1178 <application>Privoxy</application> can't intercept traffic itself,
1179 but it can handle requests that where intercepted and redirected
1180 with a packet filter (like PF or iptables), as long as the Host
1184 As the Host header is required by HTTP/1.1 and as most web sites
1185 don't work if it isn't set, this limitation shouldn't be a problem.
1188 Please refer to your packet filter's documentation to learn how to
1189 intercept and redirect traffic into Privoxy. Afterward you just have
1190 to configure Privoxy to
1191 <ulink url="../user-manual/config.html#ACCEPT-INTERCEPTED-REQUESTS">accept intercepted requests</ulink>.
1196 <sect2 renderas="sect3" id="outlook">
1197 <title>How can I configure Privoxy for use with Outlook
1200 <application>Outlook Express</application> uses <application>Internet Explorer</application>
1201 components to both render HTML, and fetch any HTTP requests that may be embedded in an HTML email.
1202 So however you have <application>Privoxy</application> configured to work
1203 with IE, this configuration should automatically be shared.
1207 <sect2 renderas="sect3" id="outlook-more">
1208 <title>How can I have separate rules just for HTML mail?</title>
1210 The short answer is, you can't. <application>Privoxy</application> has no way
1211 of knowing which particular application makes a request, so there is no way to
1212 distinguish between web pages and HTML mail.
1213 <application>Privoxy</application> just blindly proxies all requests. In the
1214 case of <application>Outlook Express</application> (see above), OE uses
1215 IE anyway, and there is no way for <application>Privoxy</application> to ever
1216 be able to distinguish between them (nor could any other proxy type application for
1220 For a good discussion of some of the issues involved (including privacy and
1221 security issues), see
1222 <ulink url="http://sourceforge.net/tracker/?func=detail&atid=211118&aid=629518&group_id=11118">http://sourceforge.net/tracker/?func=detail&atid=211118&aid=629518&group_id=11118</ulink>.
1226 <sect2 renderas="sect3" id="sneaky-cookies">
1227 <title>I sometimes notice cookies sneaking through. How?</title>
1230 url="http://en.wikipedia.org/wiki/Browser_cookie">Cookies</ulink> can be
1231 set in several ways. The classic method is via the
1232 <literal>Set-Cookie</literal> HTTP header. This is straightforward, and an
1233 easy one to manipulate, such as the &my-app; concept of
1234 <ulink url="../user-manual/actions-file.html#SESSION-COOKIES-ONLY">session-cookies-only</ulink>.
1235 There is also the possibility of using
1236 <ulink url="http://en.wikipedia.org/wiki/Javascript">Javascript</ulink> to
1237 set cookies (&my-app; calls these <literal>content-cookies</literal>). This
1238 is trickier because the syntax can vary widely, and thus requires a certain
1239 amount of guesswork. It is not realistic to catch all of these short of
1240 disabling Javascript, which would break many sites. And lastly, if the
1241 cookies are embedded in a HTTPS/SSL secure session via Javascript, they are beyond
1242 <application>Privoxy's</application> reach.
1245 All in all, &my-app; can help manage cookies in general, can help minimize
1246 the loss of privacy posed by cookies, but can't realistically stop all
1251 <sect2 renderas="sect3" id="evil-cookies">
1252 <title>Are all cookies bad? Why?</title>
1254 No, in fact there are many beneficial uses of
1256 url="http://en.wikipedia.org/wiki/Browser_cookie">cookies</ulink>. Cookies are just a
1257 method that browsers can use to store data between pages, or between browser
1258 sessions. Sometimes there is a good reason for this, and the user's life is a
1259 bit easier as a result. But there is a long history of some websites taking
1260 advantage of this layer of trust, and using the data they glean from you and
1261 your browsing habits for their own purposes, and maybe to your potential
1262 detriment. Such sites are using you and storing their data on your system.
1263 That is why the privacy conscious watch from whom those cookies come, and why
1264 they really <emphasis>need</emphasis> to be there.
1268 <ulink url="http://en.wikipedia.org/wiki/Browser_cookie">Wikipedia cookie
1269 definition</ulink> for more.
1273 <sect2 renderas="sect3" id="allow-cookies">
1274 <title>How can I allow permanent cookies for my trusted sites?</title>
1277 There are several actions that relate to cookies. The default behavior is to
1278 allow only <quote>session cookies</quote>, which means the cookies only last
1279 for the current browser session. This eliminates most kinds of abuse related
1280 to cookies. But there may be cases where you want cookies to last.
1283 To disable all cookie actions, so that cookies are allowed unrestricted,
1284 both in and out, for <literal>example.com</literal>:
1288 { -crunch-incoming-cookies -crunch-outgoing-cookies -session-cookies-only -filter{content-cookies} }
1289 .example.com</screen>
1292 Place the above in <filename>user.action</filename>. Note that some of these may
1293 be off by default anyway, so this might be redundant, but there is no harm
1294 being explicit in what you want to happen. <filename>user.action</filename>
1295 includes an alias for this situation, called
1296 <literal>allow-all-cookies</literal>.
1300 <sect2 renderas="sect3" id="multiples">
1301 <title>Can I have separate configurations for different users?</title>
1303 Each instance of <application>Privoxy</application> has its own
1304 configuration, including such attributes as the TCP port that it listens on.
1305 What you can do is run multiple instances of <application>Privoxy</application>, each with
1307 <ulink url="../user-manual/config.html#LISTEN-ADDRESS">listen-address</ulink>
1308 configuration setting, and configuration path, and then
1309 each of these can have their own configurations. Think of it as per-port
1313 Simple enough for a few users, but for large installations, consider having
1314 groups of users that might share like configurations.
1318 <sect2 renderas="sect3" id="whitelists">
1319 <title>Can I set-up Privoxy as a whitelist of
1320 <quote>good</quote> sites?</title>
1322 Sure. There are a couple of things you can do for simple white-listing.
1323 Here's one real easy one:
1326 ############################################################
1328 ############################################################
1329 { <ulink url="../user-manual/actions-file.html#BLOCK">+block</ulink> }
1330 / # Block *all* URLs
1332 ############################################################
1334 ############################################################
1335 { <ulink url="../user-manual/actions-file.html#BLOCK">-block</ulink> }
1338 games.example.com</screen>
1340 This allows access to only those three sites by first blocking all URLs, and
1341 then subsequently allowing three specific exceptions.
1344 A more interesting approach is <application>Privoxy's</application>
1345 <literal>trustfile</literal> concept, which incorporates the notion of
1346 <quote>trusted referrers</quote>. See the <ulink
1347 url="../user-manual/config.html#TRUSTFILE">User Manual Trust</ulink>
1351 These are fairly simple approaches and are not completely foolproof. There
1352 are various other configuration options that should be disabled (described
1353 elsewhere here and in <ulink url="../user-manual/">the User Manual</ulink>)
1354 so that users can't modify their own configuration and easily circumvent the
1359 <sect2 renderas="sect3" id="no-adblock">
1360 <title>How can I turn off ad-blocking?</title>
1362 Ad blocking is achieved through a complex application of various &my-app;
1363 <ulink url="../user-manual/actions-file.html">actions</ulink>. These
1364 actions are deployed against simple images, banners, flash animations,
1365 text pages, JavaScript, pop-ups and pop-unders, etc., so its not as simple as
1366 just turning one or two actions off. The various actions that make up
1367 &my-app; ad blocking are hard-coded into the default configuration files. It
1368 has been assumed that everyone using &my-app; is interested in this
1372 If you want to do without this, there are several approaches you can take:
1373 You can manually undo the many block rules in
1374 <filename>default.action</filename>. Or even easier, just create your own
1375 <filename>default.action</filename> file from scratch without the many ad
1376 blocking rules, and corresponding exceptions. Or lastly, if you are not
1377 concerned about the additional blocks that are done for privacy reasons, you
1378 can very easily over-ride <emphasis>all</emphasis> blocking with the
1379 following very simple rule in your <filename>user.action</filename>:
1383 # Unblock everybody, everywhere
1384 { <ulink url="../user-manual/actions-file.html#BLOCK">-block</ulink> }
1385 / # UN-Block *all* URLs</screen>
1388 Or even a more comprehensive reversing of various ad related actions:
1392 # Unblock everybody, everywhere, and turn off appropriate filtering, etc
1393 { <ulink url="../user-manual/actions-file.html#BLOCK">-block</ulink> \
1394 <ulink url="../user-manual/actions-file.html#FILTER-BANNERS-BY-SIZE">-filter{banners-by-size}</ulink> \
1395 <ulink url="../user-manual/actions-file.html#FILTER-BANNERS-BY-LINK">-filter{banners-by-link}</ulink> \
1396 <literal>allow-popups</literal> \
1398 / # UN-Block *all* URLs and allow ads</screen>
1401 This last <quote>action</quote> in this compound statement,
1402 <literal>allow-popups</literal>, is an <ulink
1403 url="../user-manual/actions-file.html#ALIASES">alias</ulink> that disables
1404 various pop-up blocking features.
1408 <sect2 renderas="sect3" id="templates">
1409 <title>How can I have custom template pages, like the
1410 <emphasis>BLOCKED</emphasis> page?</title>
1412 &my-app; <quote>templates</quote> are specialized text files utilized by
1413 &my-app; for various purposes and can easily be modified using any text
1414 editor. All the template pages are installed in a sub-directory appropriately
1415 named: <filename>templates</filename>. Knowing something about HTML syntax
1416 will of course be helpful. You cannot rename any of these files, or create
1417 completely new templates, that is not possible. But you can change the page
1418 content to whatever you like. Be forewarned that these files are subject to
1419 being overwritten during upgrades, so be sure to save any customizations.
1423 <sect2 renderas="sect3" id="blockall">
1424 <title>How can I remove the <quote>Go There Anyway</quote> link from
1425 the <emphasis>BLOCKED</emphasis> page?</title>
1427 There is more than one way to do it.
1430 Editing the BLOCKED template page (see above) may dissuade some users, but
1431 this method is easily circumvented. Where you need this level of control, you
1432 should build &my-app; from source, and enable various features that are
1433 available as compile-time options. You should
1434 <command>configure</command> the sources as follows:
1438 ./configure --disable-toggle --disable-editor --disable-force</screen>
1441 This will create an executable with hard-coded security features so that
1442 &my-app; does not allow easy bypassing of blocked sites, or changing the
1443 current configuration via any connected user's web browser.
1446 Note that all of these features can also be toggled on/off via options in
1447 <application>Privoxy's</application> main <ulink
1448 url="../user-manual/config.html#ACCESS-CONTROL">config</ulink> file which
1449 means you don't have to recompile anything.
1455 <!-- ~ End section ~ -->
1458 <!-- ~~~~~ New section ~~~~~ -->
1460 <sect1 id="misc"><title>Miscellaneous</title>
1462 <sect2 renderas="sect3">
1463 <title id="slowsme">How much does Privoxy slow my browsing down? This
1464 has to add extra time to browsing.</title>
1466 How much of an impact depends on many things, including the CPU of the host
1467 system, how aggressive the configuration is, which specific actions are being triggered,
1468 the size of the page, the bandwidth of the connection, etc.
1471 Overall, it should not slow you down any in real terms, and may actually help
1472 speed things up since ads, banners and other junk are not typically being
1473 retrieved and displayed. The actual processing time required by
1474 <application>Privoxy</application> itself for each page, is relatively small
1475 in the overall scheme of things, and happens very quickly. This is typically
1476 more than offset by time saved not downloading and rendering ad images (if ad
1477 blocking is being used).
1481 <quote>Filtering</quote> content via the <literal><ulink
1482 url="../user-manual/actions-file.html#FILTER">filter</ulink></literal> or
1484 url="../user-manual/actions-file.html#DEANIMATE-GIFS">deanimate-gifs</ulink></literal>
1485 actions may cause a perceived slowdown, since the entire document
1486 needs to be buffered before displaying. And on very large documents, filtering may have
1487 some measurable impact. How much depends on the page size, the actual
1488 definition of the filter(s), etc. See below. Most other actions have little
1489 to no impact on speed.
1492 Also, when filtering is enabled but zlib support isn't available, compression
1493 is often disabled (see <ulink
1494 url="../user-manual/actions-file.html#PREVENT-COMPRESSION">prevent-compression</ulink>).
1495 This can have an impact on speed as well. Again, the page size, etc. will
1496 determine how much of an impact.
1502 <sect2 renderas="sect3" id="loadingtimes"><title>I notice considerable
1503 delays in page requests compared to the old Junkbuster. What's wrong?</title>
1505 If you use any <literal><ulink
1506 url="../user-manual/actions-file.html#FILTER">filter</ulink></literal> action,
1507 such as filtering banners by size, web-bugs etc, or the <literal><ulink
1508 url="../user-manual/actions-file.html#DEANIMATE-GIFS">deanimate-gifs</ulink></literal>
1509 action, the entire document must be loaded into memory in order for the filtering
1510 mechanism to work, and nothing is sent to the browser during this time.
1513 The loading time typically does not really change much in real numbers, but
1514 the feeling is different, because most browsers are able to start rendering
1515 incomplete content, giving the user a feeling of "it works". This effect is
1516 more noticeable on slower dialup connections. Extremely large documents
1517 may have some impact on the time to load the page where there is filtering
1518 being done. But overall, the difference should be very minimal. If there is a
1519 big impact, then probably some other situation is contributing (like
1520 anti-virus software).
1523 Filtering is automatically disabled for inappropriate MIME types. But note
1524 that if the web server mis-reports the MIME type, then content that should
1525 not be filtered, could be. <application>Privoxy</application> only knows how
1526 to differentiate filterable content because of the MIME type as reported by
1527 the server, or because of some configuration setting that enables/disables
1532 <sect2 renderas="sect3" id="configurl"><title>What are "http://config.privoxy.org/" and
1533 "http://p.p/"?</title>
1535 <ulink url="http://config.privoxy.org/">http://config.privoxy.org/</ulink> is the
1536 address of <application>Privoxy</application>'s built-in user interface, and
1537 <ulink url="http://p.p/">http://p.p/</ulink> is a shortcut for it.
1540 Since <application>Privoxy</application> sits between your web browser and the Internet,
1541 it can simply intercept requests for these addresses and answer them with its built-in
1542 <quote>web server</quote>.
1545 This also makes for a good test for your browser configuration: If entering the
1546 URL <ulink url="http://config.privoxy.org/">http://config.privoxy.org/</ulink>
1547 takes you to a page saying <quote>This is Privoxy ...</quote>, everything is OK.
1548 If you get a page saying <quote>Privoxy is not working</quote> instead, then
1549 your browser didn't use <application>Privoxy</application> for the request,
1550 hence it could not be intercepted, and you have accessed the <emphasis>real</emphasis>
1551 web site at config.privoxy.org.
1554 With recent versions of <application>Privoxy</application> (version 2.9.x and
1555 later), the user interface features information on the run time status, the
1556 configuration, and even a built-in editor for the <ulink
1557 url="../user-manual/actions-file.html">actions files</ulink>.
1561 Note that the built-in URLs from earlier versions of <application>Junkbuster</application>
1562 / <application>Privoxy</application>, http://example.com/show-proxy-args and http://i.j.b/,
1563 are no longer supported. If you still use such an old version, you should really consider
1564 upgrading to &p-version;.
1569 out of date 09/02/06 HB
1570 <sect2 renderas="sect3" id="blocklist"><title>Do you still maintain the blocklists?</title>
1572 No. The patterns for blocking now reside (among other things) in the <ulink
1573 url="../user-manual/actions-file.html">actions files</ulink>, which are
1574 actively maintained instead. See next question ...
1578 <sect2 renderas="sect3" id="newads"><title>How can I submit new ads, or report
1581 Please see the <link linkend="contact">Contact section</link> for
1582 various ways to interact with the developers.
1587 <sect2 renderas="sect3" id="newads2"><title>If I do submit missed ads, will
1588 they be included in future updates?</title>
1590 Whether such submissions are eventually included in the
1591 <filename>default.action</filename> configuration file depends on how
1592 significant the issue is. We of course want to address any potential
1593 problem with major, high-profile sites such as <citetitle>Google</citetitle>,
1594 <citetitle>Yahoo</citetitle>, etc. Any site with global or regional reach,
1595 has a good chance of being a candidate. But at the other end of the spectrum
1596 are any number of smaller, low-profile sites such as for local clubs or
1597 schools. Since their reach and impact are much less, they are best handled by
1598 inclusion in the user's <filename>user.action</filename>, and thus would be
1599 unlikely to be included.
1605 <sect2 renderas="sect3" id="noonecares"><title>Why doesn't anyone answer my support
1608 Rest assured that it has been read and considered. Why it is not answered,
1609 could be for various reasons, including no one has a good answer for it, no
1610 one has had time to yet investigate it thoroughly, it has been reported
1611 numerous times already, or because not enough information was provided to help
1612 us help you. Your efforts are not wasted, and we do appreciate them.
1618 <sect2 renderas="sect3" id="ip"><title>How can I hide my IP address?</title>
1620 If you run both the browser and &my-app; locally, you cannot hide your IP
1621 address with <application>Privoxy</application> or ultimately any other
1622 software alone. The server needs to know your IP address so that it knows
1623 where to send the responses back.
1626 There are many publicly usable "anonymous" proxies out there, which
1627 provide a further level of indirection between you and the web server.
1630 However, these proxies are called "anonymous" because you don't need
1631 to authenticate, not because they would offer any real anonymity.
1632 Most of them will log your IP address and make it available to the
1633 authorities in case you violate the law of the country they run in. In fact
1634 you can't even rule out that some of them only exist to *collect* information
1635 on (those suspicious) people with a more than average preference for privacy.
1638 Your best bet is to chain <application>Privoxy</application>
1639 with <ulink url="http://tor.eff.org/">Tor</ulink>,
1640 an <ulink url="http://www.eff.org/">EFF</ulink> supported onion routing system.
1641 The configuration details can be found in
1642 <ulink url="#TOR">How do I use <application>Privoxy</application> together
1643 with <application>Tor</application> section</ulink>
1648 <sect2 renderas="sect3">
1649 <title id="anonforsure">Can Privoxy guarantee I am anonymous?</title>
1651 No. Your chances of remaining anonymous are greatly improved, but unless you
1652 <ulink url="#TOR">chain <application>Privoxy</application> with <application>Tor</application></ulink>
1653 or a similar system and know what you're doing when it comes to configuring
1654 the rest of your system, it would be safest to assume that everything you do
1655 on the Web can be traced back to you.
1658 <application>Privoxy</application> can remove various information about you,
1659 and allows <emphasis>you</emphasis> more freedom to decide which sites
1660 you can trust, and what details you want to reveal. But it neither
1661 hides your IP address, nor can it guarantee that the rest of the system
1662 behaves correctly. There are several possibilities how a web sites can find
1663 out who you are, even if you are using a strict <application>Privoxy</application>
1664 configuration and chained it with <application>Tor</application>.
1667 Most of <application>Privoxy's</application> privacy-enhancing features can be easily subverted
1668 by an insecure browser configuration, therefore you should use a browser that can
1669 be configured to only execute code from trusted sites, and be careful which sites you trust.
1670 For example there is no point in having <application>Privoxy</application>
1671 modify the User-Agent header, if websites can get all the information they want
1672 through JavaScript, ActiveX, Flash, Java etc.
1675 A few browsers disclose the user's email address in certain situations, such
1676 as when transferring a file by FTP. <application>Privoxy</application>
1677 does not filter FTP. If you need this feature, or are concerned about the
1678 mail handler of your browser disclosing your email address, you might
1679 consider products such as <application>NSClean</application>.
1682 Browsers available only as binaries could use non-standard headers to give
1683 out any information they can have access to: see the manufacturer's license
1684 agreement. It's impossible to anticipate and prevent every breach of privacy
1685 that might occur. The professionally paranoid prefer browsers available as
1686 source code, because anticipating their behavior is easier. Trust the source,
1692 <sect2 renderas="sect3">
1693 <title id="proxytest">A test site says I am not using a Proxy.</title>
1695 Good! Actually, they are probably testing for some other kinds of proxies.
1696 Hiding yourself completely would require additional steps.
1700 <sect2 renderas="sect3" id="tor"><title>How do I use Privoxy
1701 together with Tor?</title>
1703 Before you configure <application>Privoxy</application> to use <application>Tor</application>
1704 (<ulink url="http://tor.eff.org/">http://tor.eff.org/</ulink>),
1705 please follow the <citetitle>User Manual</citetitle> chapters
1706 <ulink url="../user-manual/installation.html">2. Installation</ulink> and
1707 <ulink url="../user-manual/startup.html">5. Startup</ulink> to make sure
1708 <application>Privoxy</application> itself is setup correctly.
1711 If it is, refer to <ulink url="http://tor.eff.org/documentation.html.en">Tor's
1712 extensive documentation</ulink> to learn how to install <application>Tor</application>,
1713 and make sure <application>Tor</application>'s logfile says that
1714 <quote>Tor has successfully opened a circuit</quote> and it
1715 <quote>looks like client functionality is working</quote>.
1718 If either <application>Tor</application> or <application>Privoxy</application>
1719 isn't working, their combination most likely will neither. Testing them on their
1720 own will also help you to direct problem reports to the right audience.
1721 If <application>Privoxy</application> isn't working, don't bother the
1722 <application>Tor</application> developers. If <application>Tor</application>
1723 isn't working, don't send bug reports to the <application>Privoxy</application> Team.
1726 If you verified that <application>Privoxy</application> and <application>Tor</application>
1727 are working, it is time to connect them. As far as <application>Privoxy</application>
1728 is concerned, <application>Tor</application> is just another proxy that can be reached
1729 by socks4 or socks4a. Most likely you are interested in <application>Tor</application>
1730 to increase your anonymity level, therefore you should use socks4a, to make sure DNS requests are
1731 done through <application>Tor</application> and thus invisible to your local network.
1736 Since <application>Privoxy</application> 3.0.5, its
1737 <ulink url="../user-manual/config.html">main configuration file</ulink>
1738 is already prepared for <application>Tor</application>, if you are using a
1739 default <application>Tor</application> configuration and run it on the same
1740 system as &my-app;, you just have to edit the
1741 <ulink url="../user-manual/config.html#FORWARDING">forwarding section</ulink>
1742 and uncomment the line:
1746 # forward-socks4a / 127.0.0.1:9050 .
1750 This is enough to reach the Internet, but additionally you might want to
1751 uncomment the following forward rules, to make sure your local network is still
1752 reachable through Privoxy:
1756 # forward 192.168.*.*/ .
1757 # forward 10.*.*.*/ .
1758 # forward 127.*.*.*/ .
1762 Unencrypted connections to systems in these address ranges will
1763 be as (un)secure as the local network is, but the alternative is
1764 that your browser can't reach the network at all. Then again,
1765 that may actually be desired and if you don't know for sure
1766 that your browser has to be able to reach the local network,
1767 there's no reason to allow it.
1770 If you want your browser to be able to reach servers in your local
1771 network by using their names, you will need additional exceptions
1772 that look like this:
1776 # forward localhost/ .
1780 Save the modified configuration file and open
1781 <ulink url="http://config.privoxy.org/show-status">http://config.privoxy.org/show-status/</ulink>
1782 in your browser, confirm that <application>Privoxy</application> has reloaded its configuration
1783 and that there are no other forward lines, unless you know that you need them. If everything looks good,
1785 <ulink url="http://wiki.noreply.org/noreply/TheOnionRouter/TorFAQ#head-0e1cc2ac330ede8c6ad1ac0d0db0ac163b0e6143">Tor
1786 Faq 4.2</ulink> to learn how to verify that you are really using <application>Tor</application>.
1789 Afterward, please take the time to at least skim through the rest
1790 of <application>Tor's</application> documentation. Make sure you understand
1791 what <application>Tor</application> does, why it is no replacement for
1792 application level security, and why you shouldn't use it for unencrypted logins.
1796 <sect2 renderas="sect3">
1797 <title id="sitebreak">Might some things break because header information or
1798 content is being altered?</title>
1801 Definitely. It is common for sites to use browser type, browser version,
1802 HTTP header content, and various other techniques in order to dynamically
1803 decide what to display and how to display it. What you see, and what I see,
1804 might be very different. There are many, many ways that this can be handled,
1805 so having hard and fast rules, is tricky.
1809 The <quote>User-Agent</quote> is sometimes used in this way to identify
1810 the browser, and adjust content accordingly.
1814 Also, different browsers use different encodings of Russian and Czech
1815 characters, certain web servers convert pages on-the-fly according to the
1816 User Agent header. Giving a <quote>User Agent</quote> with the wrong
1817 operating system or browser manufacturer causes some sites in these languages
1818 to be garbled; Surfers to Eastern European sites should change it to
1819 something closer. And then some page access counters work by looking at the
1820 <quote>Referer</quote> header; they may fail or break if unavailable. The
1821 weather maps of Intellicast have been blocked by their server when no
1822 <quote>Referer</quote> or cookie is provided, is another example. (But you
1823 can forge both headers without giving information away). There are
1824 many other ways things that can go wrong when trying to fool a web server. The
1825 results of which could inadvertently cause pages to load incorrectly,
1826 partially, or even not at all. And there may be no obvious clues as to just
1827 what went wrong, or why. Nowhere will there be a message that says
1828 <quote><emphasis>Turn off <literal>fast-redirects</literal> or else!</emphasis>
1833 Similar thoughts apply to modifying JavaScript, and, to a lesser degree,
1838 If you have problems with a site, you will have to adjust your configuration
1839 accordingly. Cookies are probably the most likely adjustment that may
1840 be required, but by no means the only one.
1846 <sect2 renderas="sect3">
1847 <title id="caching">Can Privoxy act as a <quote>caching</quote> proxy to
1848 speed up web browsing?</title>
1850 No, it does not have this ability at all. You want something like
1851 <ulink url="http://www.squid-cache.org/">Squid</ulink> or
1852 <ulink url="http://www.pps.jussieu.fr/~jch/software/polipo/">Polipo</ulink> for this.
1853 And, yes, before you ask, <application>Privoxy</application> can co-exist
1854 with other kinds of proxies like <application>Squid</application>.
1855 See the <ulink url="../user-manual/config.html#FORWARDING">forwarding
1856 chapter</ulink> in the <ulink url="../user-manual/index.html">user
1857 manual</ulink> for details.
1861 <sect2 renderas="sect3">
1862 <title id="firewall">What about as a firewall? Can Privoxy protect me?</title>
1864 Not in the way you mean, or in the way some firewall vendors claim they can.
1865 <application>Privoxy</application> can help protect your privacy, but can't
1866 protect your system from intrusion attempts. It is, of course, perfectly possible
1867 to use <emphasis>both</emphasis>.
1871 <sect2 renderas="sect3">
1872 <title id="wasted">I have large empty spaces / a checkerboard pattern now where
1873 ads used to be. Why?</title>
1875 It is technically possible to eliminate banners and ads in a way that frees
1876 their allocated page space. This could easily be done by blocking with
1877 <application>Privoxy's</application> filters,
1878 and eliminating the <emphasis>entire</emphasis> image references from the
1882 But, this would consume considerably more CPU resources (IOW, slow things
1883 down), would likely destroy the layout of some web pages which rely on the
1884 banners utilizing a certain amount of page space, and might fail in other
1885 cases, where the screen space is reserved (e.g. by HTML tables for instance).
1886 Also, making ads and banners disappear without any trace complicates
1887 troubleshooting, and would sooner or later be problematic.
1890 The better alternative is to instead let them stay, and block the resulting
1891 requests for the banners themselves as is now the case. This leaves either
1892 empty space, or the familiar checkerboard pattern.
1895 So the developers won't support this in the default configuration, but you
1896 can of course define appropriate filters yourself to achieve this.
1900 <sect2 renderas="sect3">
1901 <title id="ssl">How can Privoxy filter Secure (HTTPS) URLs?</title>
1903 Since secure HTTP connections are encrypted SSL sessions between your browser
1904 and the secure site, and are meant to be reliably <emphasis>secure</emphasis>,
1905 there is little that <application>Privoxy</application> can do but hand the raw
1906 gibberish data though from one end to the other unprocessed.
1909 The only exception to this is blocking by host patterns, as the client needs
1910 to tell <application>Privoxy</application> the name of the remote server,
1911 so that <application>Privoxy</application> can establish the connection.
1912 If that name matches a host-only pattern, the connection will be blocked.
1915 As far as ad blocking is concerned, this is less of a restriction than it may
1916 seem, since ad sources are often identifiable by the host name, and often
1917 the banners to be placed in an encrypted page come unencrypted nonetheless
1918 for efficiency reasons, which exposes them to the full power of
1919 <application>Privoxy</application>'s ad blocking.
1922 <quote>Content cookies</quote> (those that are embedded in the actual HTML or
1923 JS page content, see <literal><ulink
1924 url="../user-manual/actions-file.html#FILTER-CONTENT-COOKIES">filter{content-cookies}</ulink></literal>),
1925 in an SSL transaction will be impossible to block under these conditions.
1926 Fortunately, this does not seem to be a very common scenario since most
1927 cookies come by traditional means.
1932 <sect2 renderas="sect3">
1933 <title id="secure">Privoxy runs as a <quote>server</quote>. How
1934 secure is it? Do I need to take any special precautions?</title>
1936 On Unix-like systems, <application>Privoxy</application> can run as a non-privileged
1937 user, which is how we recommend it be run. Also, by default
1938 <application>Privoxy</application> listens to requests from <quote>localhost</quote>
1942 The server aspect of <application>Privoxy</application> is not itself directly
1943 exposed to the Internet in this configuration. If you want to have
1944 <application>Privoxy</application> serve as a LAN proxy, this will have to
1945 be opened up to allow for LAN requests. In this case, we'd recommend
1946 you specify only the LAN gateway address, e.g. 192.168.1.1, in the main
1947 <application>Privoxy</application> configuration file and check all <ulink
1948 url="../user-manual/config.html#ACCESS-CONTROL">access control and security
1949 options</ulink>. All LAN hosts can then use this as their proxy address
1950 in the browser proxy configuration, but <application>Privoxy</application>
1951 will not listen on any external interfaces. ACLs can be defined in addition,
1952 and using a firewall is always good too. Better safe than sorry.
1957 <sect2 renderas="sect3" id="turnoff">
1958 <title>How can I temporarily disable Privoxy?</title>
1960 The easiest way is to access <application>Privoxy</application> with your
1961 browser by using the remote toggle URL: <ulink
1962 url="http://config.privoxy.org/toggle">http://config.privoxy.org/toggle</ulink>.
1963 See the <ulink url="../user-manual/appendix.html#BOOKMARKLETS">Bookmarklets section</ulink>
1964 of the <citetitle>User Manual</citetitle> for an easy way to access this
1970 <sect2 renderas="sect3" id="reallyoff">
1971 <title>When <quote>disabled</quote> is Privoxy totally
1972 out of the picture?</title>
1974 No, this just means all optional filtering and actions are disabled.
1975 <application>Privoxy</application> is still acting as a proxy, but just not
1976 doing any of the things that <application>Privoxy</application> would
1977 normally be expected to do. It is still a <quote>middle-man</quote> in
1978 the interaction between your browser and web sites. See below to bypass
1983 <sect2 renderas="sect3" id="turnoff2">
1984 <title>How can I tell Privoxy to totally ignore certain sites?</title>
1986 Bypassing a proxy, or proxying based on arbitrary criteria, is purely a browser
1987 configuration issue, not a &my-app; issue. Modern browsers typically do have
1988 settings for not proxying certain sites. Check your browser's help files.
1993 <sect2 renderas="sect3" id="crunch">
1994 <title>My logs show Privoxy <quote>crunches</quote>
1995 ads, but also its own internal CGI pages. What is a <quote>crunch</quote>?</title>
1997 A <quote>crunch</quote> simply means <application>Privoxy</application> intercepted
1998 <emphasis>something</emphasis>, nothing more. Often this is indeed ads or
1999 banners, but <application>Privoxy</application> uses the same mechanism for
2000 trapping requests for its own internal pages. For instance, a request for
2001 <application>Privoxy's</application> configuration page at: <ulink
2002 url="http://config.privoxy.org">http://config.privoxy.org</ulink>, is
2003 intercepted (i.e. it does not go out to the 'net), and the familiar CGI
2004 configuration is returned to the browser, and the log consequently will show
2005 a <quote>crunch</quote>.
2008 Since version 3.0.7, Privoxy will also log the crunch reason.
2009 If you are using an older version you might want to upgrade.
2013 <sect2 renderas="sect3" id="downloads">
2014 <title>Can Privoxy effect files that I download
2015 from a webserver? FTP server?</title>
2017 From the webserver's perspective, there is no difference between
2018 viewing a document (i.e. a page), and downloading a file. The same is true of
2019 <application>Privoxy</application>. If there is a match for a <literal><ulink
2020 url="../user-manual/actions-file.html#BLOCK">block</ulink></literal> pattern,
2021 it will still be blocked, and of course this is obvious.
2024 Filtering is potentially more of a concern since the results are not always
2025 so obvious, and the effects of filtering are there whether the file is simply
2026 viewed, or downloaded. And potentially whether the content is some obnoxious
2027 advertisement, or Mr. Jimmy's latest/greatest source code jewel. Of course,
2028 one of these presumably is <quote>bad</quote> content that we don't want, and
2029 the other is <quote>good</quote> content that we do want.
2030 <application>Privoxy</application> is blind to the differences, and can only
2031 distinguish <quote>good from bad</quote> by the configuration parameters
2032 <emphasis>we</emphasis> give it.
2035 <application>Privoxy</application> knows the differences in files according
2036 to the <quote>Content Type</quote> as reported by the webserver. If this is
2037 reported accurately (e.g. <quote>application/zip</quote> for a zip archive),
2038 then <application>Privoxy</application> knows to ignore these where
2039 appropriate. <application>Privoxy</application> potentially can filter HTML
2040 as well as plain text documents, subject to configuration parameters of
2041 course. Also, documents that are of an unknown type (generally assumed to be
2042 <quote>text/plain</quote>) can be filtered, as will those that might be
2043 incorrectly reported by the webserver. If such a file is a downloaded file
2044 that is intended to be saved to disk, then any content that might have been
2045 altered by filtering, will be saved too, for these (probably rare) cases.
2048 Note that versions later than 3.0.2 do NOT filter document types reported as
2049 <quote>text/plain</quote>. Prior to this, <application>Privoxy</application>
2050 did filter this document type.
2053 In short, filtering is <quote>ON</quote> if a) the content type as reported
2054 by the webserver is appropriate <emphasis>and</emphasis> b) the configuration
2055 allows it (or at least does not disallow it). That's it. There is no magic
2056 cookie anywhere to say this is <quote>good</quote> and this is
2057 <quote>bad</quote>. It's the configuration that lets it all happen or not.
2060 If you download text files, you probably do not want these to be filtered,
2061 particularly if the content is source code, or other critical content. Source
2062 code sometimes might be mistaken for Javascript (i.e. the kind that might
2063 open a pop-up window). It is recommended to turn off filtering for download
2064 sites (particularly if the content may be plain text files and you are using
2065 version 3.0.2 or earlier) in your <filename>user.action</filename> file. And
2066 also, for any site or page where making <emphasis>any</emphasis> changes at
2067 all to the content is to be avoided.
2070 <application>Privoxy</application> does not do FTP at all, only HTTP
2071 and HTTPS (SSL) protocols, so please don't try.
2075 <sect2 renderas="sect3" id="downloads2">
2076 <title>I just downloaded a Perl script, and Privoxy
2077 altered it! Yikes, what is wrong!</title>
2083 <sect2 renderas="sect3" id="hostsfile">
2084 <title>Should I continue to use a <quote>HOSTS</quote> file for ad-blocking?</title>
2086 One time-tested technique to defeat common ads is to trick the local DNS
2087 system by giving a phony IP address for the ad generator in the local
2088 <filename>HOSTS</filename> file, typically using <literal>127.0.0.1</literal>, aka
2089 <literal>localhost</literal>. This effectively blocks the ad.
2092 There is no reason to use this technique in conjunction with
2093 <application>Privoxy</application>. <application>Privoxy</application>
2094 does essentially the same thing, much more elegantly and with much more
2095 flexibility. A large <filename>HOSTS</filename> file, in fact, not only
2096 duplicates effort, but may get in the way and seriously slow down your system.
2097 It is recommended to remove such entries from your <filename>HOSTS</filename> file. If you think
2098 your hosts list is neglected by <application>Privoxy's </application>
2099 configuration, consider adding your list to your <filename>user.action</filename> file:
2106 ads.galore.example.com
2107 etc.example.com</screen>
2111 <sect2 renderas="sect3" id="seealso">
2112 <title>Where can I find more information about Privoxy
2113 and related issues?</title>
2114 <!-- Include seealso.sgml boilerplate: -->
2116 <!-- end boilerplate -->
2121 <ulink url="../user-manual/seealso.html">user-manual</ulink> for
2127 <sect2 renderas="sect3" id="microsuck">
2128 <title>I've noticed that Privoxy changes <quote>Microsoft</quote> to
2129 <quote>MicroSuck</quote>! Why are you manipulating my browsing?</title>
2132 We're not. The text substitutions that you are seeing are disabled
2133 in the default configuration as shipped. You have either manually
2134 activated the <quote><literal>fun</literal></quote> filter which
2135 is clearly labeled <quote>Text replacements for subversive browsing
2136 fun!</quote> or you are using an older Privoxy version and have implicitly
2137 activated it by choosing the <quote>Adventuresome</quote> profile in the
2138 web-based editor. Please upgrade!
2142 <sect2 renderas="sect3" id="valid">
2143 <title>Does Privoxy produce <quote>valid</quote> HTML (or XHTML)?</title>
2146 Privoxy generates HTML in both its own <quote>templates</quote>, and possibly
2147 whenever there are text substitutions via a &my-app; filter. While this
2148 should always conform to the HTML 4.01 specifications, it has not been
2149 validated against this or any other standard.
2157 <!-- ~~~~~ New section ~~~~~ -->
2159 <sect1 id="trouble">
2160 <title>Troubleshooting</title>
2162 <sect2 renderas="sect3">
2163 <title id="refused">I cannot connect to any websites. Or, I am getting
2164 <quote>connection refused</quote> message with every web page. Why?</title>
2166 There are several possibilities:
2171 <application>Privoxy</application> is not running. Solution: verify
2172 that &my-app; is installed correctly, has not crashed, and is indeed running.
2173 Look at <application>Privoxy's</application> logs to see what they say.
2175 <listitem><para>Or your browser is configured for a different port than what
2176 <application>Privoxy</application> is using. Solution: verify that &my-app;
2177 and your browser are set to the same port (<literal>listen-address</literal>).
2179 <listitem><para>Or if using a forwarding rule, you have a configuration problem or a
2180 problem with a host in the forwarding chain. Solution: temporarily alter your
2181 configuration and take the forwarders out of the equation.
2184 Or you have a firewall that is interfering and blocking you. Solution:
2185 try disabling or removing the firewall as a simple test.
2192 <!-- ~~~~~ New section ~~~~~ -->
2193 <sect2 renderas="sect3" id="error503">
2194 <title>Why am I getting a 503 Error (WSAECONNREFUSED) on every page?</title>
2196 More than likely this is a problem with your TCP/IP networking. ZoneAlarm has
2197 been reported to cause this symptom -- even if not running! The solution is
2198 to either fight the ZA configuration, or uninstall ZoneAlarm, and then find
2199 something better behaved in its place. Other personal firewall type products
2200 may cause similar type problems if not configured correctly.
2204 <sect2 renderas="sect3">
2205 <title id="flushit">I just added a new rule, but the steenkin ad is
2206 still getting through. How?</title>
2208 If the ad had been displayed before you added its URL, it will probably be
2209 held in the browser's cache for some time, so it will be displayed without
2210 the need for any request to the server, and <application>Privoxy</application>
2211 will not be involved. Flush the browser's caches, and then try again.
2215 If this doesn't help, you probably have an error in the rule you
2216 applied. Try pasting the full URL of the offending ad into <ulink
2217 url="http://config.privoxy.org/show-url-info">http://config.privoxy.org/show-url-info</ulink>
2218 and see if it really matches your new rule. Blocking ads is like blocking
2219 spam: a lot of tinkering is required to stay ahead of the game. And
2220 remember you need to block the URL of the ad in question, which may be
2221 entirely different from the site URL itself. Most ads are hosted on different
2222 servers than the main site itself. If you right-click on the ad, you should
2223 be able to get all the relevant information you need. Alternately, you can
2224 find the correct URL by looking at <application>Privoxy's</application> logs.
2227 Below is a slightly modified real-life log snippet that originates with one
2228 requested URL: <literal>www.example.com</literal> (name of site was changed
2229 for this example, the number of requests is real). You can see in this the
2230 complexity of what goes into making up this one <quote>page</quote>. There
2231 are eight different domains involved here, with thirty two separate URLs
2232 requested in all, making up all manner of images, Shockwave Flash,
2233 JavaScript, CSS stylesheets, scripts, and other related content. Some of this
2234 content is obviously <quote>good</quote> or <quote>bad</quote>, but not all.
2235 Many of the more questionable looking requests, are going to outside domains
2236 that seem to be identifying themselves with suspicious looking names, making
2237 our job a little easier. &my-app; has <quote>crunched</quote> (meaning caught
2238 and BLOCKED) quite a few items in this example, but perhaps missed a few as well.
2243 Request: www.example.com/
2244 Request: www.example.com/favicon.ico
2245 Request: img.example.com/main.css
2246 Request: img.example.com/sr.js
2247 Request: example.betamarker.com/example.html
2248 Request: www.lik-sang.com/Banners/bestsellers/skyscraper.php?likref=BSellers
2249 Request: img.example.com/pb.png
2250 Request: www.google-analytics.com/urchin.js crunch!
2251 Request: www.advertising-department.com/ats/switch.ps.php?26856 crunch!
2252 Request: img.example.com/p.gif
2253 Request: www.popuptraffic.com/assign.php?l=example&mode=behind crunch!
2254 Request: www.popuptraffic.com/scripts/popup.php?hid=5c3cf&tmpl=PBa.tmpl crunch!
2255 Request: www.popuptraffic.com/assign.php?l=example crunch!
2256 Request: www.lik-sang.com/Banners/best_sellers/best_sellers.css
2257 Request: www.adtrak.net/adx.js crunch!
2258 Request: img.example.com/hbg.gif
2259 Request: img.example.com/example.jpg
2260 Request: img.example.com/mt.png
2261 Request: img.example.com/mm.png
2262 Request: img.example.com/mb.png
2263 Request: www.popuptraffic.com/scripts/popup.php?hid=a71b91fa5&tmpl=Ua.tmp crunch!
2264 Request: www.example.com/tracker.js
2265 Request: www.lik-sang.com/Banners/best_sellers/lsi_head.gif
2266 Request: www.adtrak.net/adjs.php?n=020548130&what=zone:61 crunch!
2267 Request: www.adtrak.net/adjs.php?n=463594413&what=zone:58&source=Ua crunch!
2268 Request: www.lik-sang.com/Banners/best_sellers/bottomani.swf
2269 Request: mmm.elitemediagroup.net/install.php?allowpop=no&popupmincook=0&allowsp2=1 crunch!
2270 Request: www.example.com/tracker.js?screen=1400x1050&win=962x693
2271 Request: www.adtrak.net/adlog.php?bannerid=1309&clientid=439&zoneid=61 crunch!
2272 Request: 66.70.21.80/scripts/click.php?hid=5c3cf599a9efd0320d26&si
2273 Request: 66.70.21.80/img/pixel.gif
2274 Request: www.adtrak.net/adlog.php?bannerid=1309&clientid=439&zoneid=58&source=Ua&block=86400 crunch!
2275 Request: 66.70.21.80/scripts/click.php?hid=a71b9f6504b0c5681fa5&si=Ua
2280 Despite 12 out of 32 requests being blocked, the page looked, and seemed to
2281 behave perfectly <quote>normal</quote> (minus some ads, of course).
2286 <sect2 id="badsite" renderas="sect3">
2287 <title >One of my favorite sites does not work with Privoxy.
2288 What can I do?</title>
2291 First verify that it is indeed a <application>Privoxy</application> problem,
2292 by toggling off <application>Privoxy</application> through <ulink
2293 url="http://config.privoxy.org/toggle">http://config.privoxy.org/toggle</ulink>,
2294 and then shift-reloading the problem page (i.e. holding down the shift key
2295 while clicking reload. Alternatively, flush your browser's disk and memory
2300 If the problem went away, we know we have a configuration related problem.
2302 url="http://config.privoxy.org/show-url-info">http://config.privoxy.org/show-url-info</ulink>
2303 and paste the full URL of the page in question into the prompt. See which
2304 actions are being applied to the URL, and which matches in which actions
2305 files are responsible for that. It might be helpful also to look at your logs
2306 for this site too, to see what else might be happening. Many sites are
2307 complex and require a number of related pages to help present their content.
2308 Look at what else might be used by the page in question, and what of that
2309 might be <emphasis>required</emphasis>.
2310 Now, armed with this information, go to
2312 url="http://config.privoxy.org/show-status">http://config.privoxy.org/show-status</ulink>
2313 and select the appropriate actions files for editing. </para>
2315 You can now either look for a section which disables the actions that
2316 you suspect to cause the problem and add a pattern for your site there,
2317 or make up a completely new section for your site. In any case, the recommended
2318 way is to disable only the prime suspect, reload the problem page, and only
2319 if the problem persists, disable more and more actions until you have
2320 identified the culprit. You may or may not want to turn the other actions
2321 on again. Remember to flush your browser's caches in between any such changes!
2324 Alternately, if you are comfortable with a text editor, you can accomplish
2325 the same thing by editing the appropriate actions file. Probably the easiest
2326 way to deal with such problems when editing by hand is to add your
2327 site to a <literal>{ fragile }</literal> section in <filename>user.action</filename>,
2328 which is an alias that turns off most <quote>dangerous</quote>
2329 actions, but is also likely to turn off more actions then needed, and thus lower
2330 your privacy and protection more than necessary,
2333 Troubleshooting actions is discussed in more detail in the <ulink
2334 url="../user-manual/appendix.html#ACTIONSANAT">User Manual appendix,
2335 Troubleshooting: the Anatomy of an Action</ulink>.
2336 There is also an <ulink
2337 url="../user-manual/actions-file.html#ACT-EXAMPLES">actions tutorial</ulink>
2338 with general configuration information and examples.
2341 As a last resort, you can always see if your browser has a setting that will
2342 bypass the proxy setting for selective sites. Modern browsers can do this.
2348 <!-- ~~~~~ New section ~~~~~ -->
2349 <sect2 id="dun" renderas="sect3">
2350 <title>After installing Privoxy, I have to log in
2351 every time I start IE. What gives?</title>
2354 This is a quirk that effects the installation of
2355 <application>Privoxy</application>, in conjunction with Internet Explorer and
2356 Internet Connection Sharing on Windows 2000 and Windows XP. The symptoms may
2357 appear to be corrupted or invalid DUN settings, or passwords.
2361 When setting up an NT based Windows system with
2362 <application>Privoxy</application> you may find that things do not seem to be
2363 doing what you expect. When you set your system up you will probably have set
2364 up Internet Connection Sharing (ICS) with Dial up Networking (DUN) when
2365 logged in with administrator privileges. You will probably have made this DUN
2366 connection available to other accounts that you may have set-up on your
2367 system. E.g. Mum or Dad sets up the system and makes accounts suitably
2368 configured for the kids.
2372 When setting up <application>Privoxy</application> in this environment you
2373 will have to alter the proxy set-up of Internet Explorer (IE) for the
2374 specific DUN connection on which you wish to use
2375 <application>Privoxy</application>. When you do this the ICS DUN set-up
2376 becomes user specific. In this instance you will see no difference if you
2377 change the DUN connection under the account used to set-up the connection.
2378 However when you do this from another user you will notice that the DUN
2379 connection changes to make available to "Me only". You will also find that
2380 you have to store the password under each different user!
2384 The reason for this is that each user's set-up for IE is user specific. Each
2385 set-up DUN connection and each LAN connection in IE store the settings for
2386 each user individually. As such this enforces individual configurations
2387 rather than common ones. Hence the first time you use a DUN connection after
2388 re-booting your system it may not perform as you expect, and prompt you for
2389 the password. Just set and save the password again and all should be OK.
2393 [Thanks to Ray Griffith for this submission.]
2398 <!-- ~~~~~ New section ~~~~~ -->
2399 <sect2 id="ftp" renderas="sect3">
2400 <title>I cannot connect to any FTP sites. Privoxy
2401 is blocking me.</title>
2403 <application>Privoxy</application> cannot act as a proxy for FTP traffic,
2404 so do not configure your browser to use <application>Privoxy</application>
2405 as an FTP proxy. The same is true for <emphasis>any protocol other than HTTP
2406 or HTTPS (SSL)</emphasis>.
2409 Most browsers understand FTP as well as HTTP. If you connect to a site, with
2410 a URL like <literal>ftp://ftp.example.com</literal>, your browser is making
2411 an FTP connection, and not a HTTP connection. So while your browser may
2412 speak FTP, <application>Privoxy</application> does not, and cannot proxy
2416 To complicate matters, some systems may have a generic <quote>proxy</quote>
2417 setting, which will enable various protocols, including
2418 <emphasis>both</emphasis> HTTP and FTP proxying! So it is possible to
2419 accidentally enable FTP proxying in these cases. And of course, if this
2420 happens, <application>Privoxy</application> will indeed cause problems since
2421 it does not know FTP. <![%p-newstuff;[Newer version will give a sane error
2422 message if a FTP connection is attempted.]]> Just disable the FTP setting
2423 and all will be well again.
2426 Will <application>Privoxy</application> ever proxy FTP traffic? Unlikely.
2427 There just is not much reason, and the work to make this happen is more than
2432 <!-- ~~~~~ New section ~~~~~ -->
2433 <sect2 id="osxie" renderas="sect3">
2434 <title>In Mac OSX, I can't configure Microsoft Internet Explorer to use
2435 Privoxy as the HTTP proxy.</title>
2437 Microsoft Internet Explorer (in versions like 5.1) respects system-wide
2438 network settings. In order to change the HTTP proxy, open System
2439 Preferences, and click on the Network icon. In the settings pane that
2440 comes up, click on the Proxies tab. Ensure the "Web Proxy (HTTP)" checkbox
2441 is checked and enter <literal>127.0.0.1</literal> in the entry field.
2442 Enter <literal>8118</literal> in the Port field. The next time you start
2443 IE, it should reflect these values.
2447 <!-- ~~~~~ New section ~~~~~ -->
2448 <sect2 renderas="sect3" id="osxuninstall">
2449 <title>In Mac OSX, I dragged the Privoxy folder to the trash in order to
2450 uninstall it. Now the finder tells me I don't have sufficient privileges to
2451 empty the trash.</title>
2453 Just dragging the <application>Privoxy</application> folder to the trash is
2454 not enough to delete it. <application>Privoxy</application> supplies an
2455 <application>uninstall.command</application> file that takes care of
2456 these details. Open the trash, drag the <application>uninstall.command</application>
2457 file out of the trash and double-click on it. You will be prompted for
2458 confirmation and the administration password.
2461 The trash may still appear full after this command; emptying the trash
2462 from the desktop should make it appear empty again.
2467 <!-- ~~~~~ New section ~~~~~ -->
2468 <sect2 renderas="sect3" id="osximages">
2469 <title>In Mac OSX Panther (10.3), images often fail to load and/or I
2470 experience random delays in page loading. I'm using
2471 <literal>localhost</literal> as my browser's proxy setting.</title>
2473 We believe this is due to an IPv6-related bug in OSX, but don't fully
2474 understand the issue yet. In any case, changing the proxy setting to
2475 <literal>127.0.0.1</literal> instead of <literal>localhost</literal>
2476 works around the problem.
2480 <!-- ~~~~~ New section ~~~~~ -->
2481 <sect2 renderas="sect3" id="blankpage">
2482 <title>I get a completely blank page at one site. <quote>View Source</quote>
2483 shows only: <markup><![CDATA[<html><body></body></html>]]></markup>. Without
2484 Privoxy the page loads fine.</title>
2486 Chances are that the site suffers from a bug in
2487 <ulink url="http://www.php.net/"><application>PHP</application></ulink>,
2488 which results in empty pages being sent if the client explicitly requests
2489 an uncompressed page, like <application>Privoxy</application> does.
2490 This bug has been fixed in PHP 4.2.3.
2493 To find out if this is in fact the source of the problem, try adding
2494 the site to a <literal>-prevent-compression</literal> section in
2495 <filename>user.action</filename>:
2498 # Make exceptions for ill-behaved sites:
2500 {-prevent-compression}
2501 .example.com</screen>
2503 If that works, you may also want to report the problem to the
2504 site's webmasters, telling them to use zlib.output_compression
2505 instead of ob_gzhandler in their PHP applications (workaround)
2506 or upgrade to PHP 4.2.3 or later (fix).
2510 <sect2 renderas="sect3" id="nohostname">
2511 <title>My logs show many <quote>Unable to get my own hostname</quote> lines.
2514 <application>Privoxy</application> tries to get the hostname of the system
2515 its running on from the IP address of the system interface it is bound to
2516 (from the <filename>config</filename> file
2517 <emphasis>listen-address</emphasis> setting). If the system cannot supply
2518 this information, <application>Privoxy</application> logs this condition.
2521 Typically, this would be considered a minor system configuration error. It is
2522 not a fatal error to <application>Privoxy</application> however, but may
2523 result in a much slower response from <application>Privoxy</application> on
2524 some platforms due to DNS timeouts.
2527 This can be caused by a problem with the local <filename>HOSTS</filename>
2528 file. If this file has been changed from the original, try reverting it to
2529 see if that helps. Make sure whatever name(s) are used for the local system,
2530 that they resolve both ways.
2534 <sect2 renderas="sect3" id="inuse">
2535 <title>When I try to launch Privoxy, I get an
2536 error message <quote>port 8118 is already in use</quote> (or similar wording).
2539 Port 8118 is <application>Privoxy's</application> default TCP
2540 <quote>listening</quote> port. Typically this message would mean that there
2541 is already one instance of <application>Privoxy</application> running, and
2542 your system is actually trying to start a second
2543 <application>Privoxy</application> on the same port, which will not work.
2544 (You can have multiple instances but they must be assigned different ports.)
2545 How and why this might happen varies from platform to platform, but you need
2546 to check your installation and start-up procedures.
2550 <sect2 renderas="sect3" id="demoronizer">
2552 Pages with UTF-8 fonts are garbled.
2555 This is caused by the <quote>demoronizer</quote> filter. You should either
2556 upgrade <application>Privoxy</application>, or at least upgrade to the most
2557 recent <filename>default.action</filename> file available from <ulink
2558 url="http://sourceforge.net/project/showfiles.php?group_id=11118">SourceForge</ulink>.
2559 Or you can simply disable the demoronizer filter.
2563 <sect2 renderas="sect3" id="demoronizer2">
2565 Why are binary files (such as images) corrupted when Privoxy
2569 This may also be caused by the <quote>demoronizer</quote> filter,
2570 in conjunction with a web server that is misreporting the content type. Binary
2571 files are exempted from <application>Privoxy's</application> filtering
2572 (unless the web server by mistake says the file is something else). Either
2573 upgrade <application>Privoxy</application>, or go to the most recent
2574 <filename>default.action</filename> file available from <ulink
2575 url="http://sourceforge.net/project/showfiles.php?group_id=11118">SourceForge</ulink>.
2579 <sect2 renderas="sect3" id="demoronizer3">
2581 What is the <quote>demoronizer</quote> and why is it there?
2584 The original demoronizer was a Perl script that cleaned up HTML pages which
2585 were created with certain Microsoft products. MS has used proprietary extensions
2586 to standardized font encodings (ISO 8859-1), which has caused problems for pages
2587 that are viewed with non-Microsoft products (and are expecting to see a
2588 standard set of fonts). The demoronizer corrected these errors so the pages
2589 displayed correctly. <application>Privoxy</application> borrowed from this
2590 script, introducing a filter based on the original demoronizer, which in turn could
2591 correct these errors on the fly.
2594 But this is only needed in some situations, and will cause serious problems in some
2598 If you are using Microsoft products, you do not need it. If you need to view
2599 pages with UTF-8 characters (such as Cyrillic or Chinese), then it will
2600 cause corruption of the fonts, and thus <emphasis>should not be on</emphasis>.
2603 On the other hand, if you use non-Microsoft products, and you occasionally
2604 notice wierd characters on pages, you might want to try it.
2608 <sect2 renderas="sect3" id="windowopen">
2610 Why do I keep seeing <quote>PrivoxyWindowOpen()</quote> in raw source code?
2613 <application>Privoxy</application> is attempting to disable malicious
2614 <ulink url="http://en.wikipedia.org/wiki/Javascript">Javascript</ulink>
2615 in this case, with the <literal>unsolicited-popups</literal>
2616 filter. <application>Privoxy</application> cannot tell very well
2617 <quote>good</quote> code snippets from <quote>bad</quote> code snippets.
2620 If you see this in HTML source, and the page displays without problems, then
2621 this is good, and likely some pop-up window was disabled. If you see this
2622 where it is causing a problem, such as a downloaded program source code file,
2623 then you should set an exception for this site or page such that the
2624 integrity of the page stays in tact by disabling all filtering.
2628 <sect2 renderas="sect3" id="dnserrors">
2630 I am getting too many DNS errors like <quote>404 No Such Domain</quote>. Why
2631 can't Privoxy do this better?
2634 There are potentially several factors here. First of all, the DNS resolution
2635 is done by the underlying operating system -- not
2636 <application>Privoxy</application> itself. <application>Privoxy</application>
2637 merely initiates the process and hands it off, and then later reports
2638 whatever the outcome was. And tries to give a coherent message if there seems
2639 to be a problem. In some cases, this might otherwise be mitigated by the
2640 browser itself which might try some work-arounds and alternate approaches (e.g
2641 adding <quote>www.</quote> to the URL). In other cases, if
2642 <application>Privoxy</application> is being chained with another proxy, this
2643 could complicate the issue, and cause undue
2644 delays and timeouts. In the case of a <quote>socks4a</quote> proxy, the socks
2645 server handles all the DNS. <application>Privoxy</application> would just be
2646 the <quote>messenger</quote> which is reporting whatever problem occurred
2647 downstream, and not the root cause of the error.
2651 In any case, newer versions include various improvements to help
2652 <application>Privoxy</application> better handle these cases.
2656 <sect2 renderas="sect3" id="allcpu">
2658 At one site Privoxy just hangs, and starts taking
2659 all CPU. Why is this?
2662 This is probably a manifestation of the <quote>100% cpu</quote> problem that
2663 occurs on pages containing many (thousands upon thousands) of blank lines. The blank lines
2664 are in the raw HTML source of the page, and the browser just ignores them. But the
2665 pattern matching in <application>Privoxy's</application> page filtering
2666 mechanism is trying to match against absurdly long strings and this becomes
2667 very CPU-intensive, taking a long, long time to complete. Until a better
2668 solution comes along, disable filtering on these pages, particularly the
2669 <literal>js-annoyances</literal> and <literal>unsolicited-popups</literal>
2674 <sect2 renderas="sect3" id="slowcrawl">
2675 <title>I just installed Privoxy, and all my
2676 browsing has slowed to a crawl. What gives? </title>
2678 This should not happen, and for the overwhelming number of users world-wide,
2679 it does not happen. I would suspect some inadvertent interaction of software
2680 components such as anti-virus software, spyware protectors, personal
2681 firewalls or similar components. Try disabling (or uninstalling) these one
2682 at a time and see if that helps.
2686 <sect2 renderas="sect3" id="preventcomp">
2687 <title>Why do my filters work on some sites but not on others? </title>
2689 It's probably due to compression. It is a common practice for web servers to
2690 send their content <quote>compressed</quote> in order to speed things up, and
2691 then let the browser <quote>uncompress</quote> them. When compiled with zlib support
2692 &my-app; can decompress content before filtering, otherwise you may want to enable
2694 url="../user-manual/actions-file.html#PREVENT-COMPRESSION">prevent-compression</ulink>.
2701 <!-- ~~~~~ New section ~~~~~ -->
2702 <sect1 id="contact"><title>Contacting the developers, Bug Reporting and Feature Requests</title>
2703 <!-- Include contacting.sgml -->
2705 <!-- end contacting -->
2708 <!-- ~~~~~ New section ~~~~~ -->
2709 <sect1 id="copyright"><title>Privoxy Copyright, License and History</title>
2711 <!-- Include copyright.sgml -->
2717 Portions of this document are <quote>borrowed</quote> from the original
2718 <application>Junkbuster</application> (tm) FAQ, and modified as
2719 appropriate for <application>Privoxy</application>.
2722 <!-- ~~~~~ New section ~~~~~ -->
2723 <sect2><title>License</title>
2724 <!-- Include copyright.sgml: -->
2726 <!-- end copyright -->
2728 <!-- ~ End section ~ -->
2730 <!-- ~~~~~ New section ~~~~~ -->
2731 <sect2><title>History</title>
2732 <!-- Include history.sgml -->
2738 <!-- ~ End section ~ -->
2741 <!-- ~~~~~ New section ~~~~~ -->
2743 <sect1 id="seealso"><title>See also</title>
2745 <!-- Include seealso.sgml -->
2756 Tue 09/11/01 06:38:14 PM EST: Test SGML doc by Hal Burgiss.
2758 This program is free software; you can redistribute it
2759 and/or modify it under the terms of the GNU General
2760 Public License as published by the Free Software
2761 Foundation; either version 2 of the License, or (at
2762 your option) any later version.
2764 This program is distributed in the hope that it will
2765 be useful, but WITHOUT ANY WARRANTY; without even the
2766 implied warranty of MERCHANTABILITY or FITNESS FOR A
2767 PARTICULAR PURPOSE. See the GNU General Public
2768 License for more details.
2770 The GNU General Public License should be included with
2771 this file. If not, you can view it at
2772 http://www.gnu.org/copyleft/gpl.html
2773 or write to the Free Software Foundation, Inc.,
2774 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
2777 Revision 2.26 2007/08/05 15:37:55 fabiankeil
2778 - Don't claim that thousands of people read our code.
2779 - Specify the GPL version and link to GPLv2 instead of v3.
2780 - Note that configuration syntax may change between releases.
2781 - Mention zlib support.
2782 - Answer the "transparent proxy" question properly.
2783 - Add "intercepting proxy" entry.
2785 - Rephrase some other sentences for various reasons.
2787 Revision 2.25 2007/07/18 11:00:34 hal9
2788 Add misc note about valid mark-up in Privoxy.
2790 Revision 2.24 2006/11/14 01:57:46 hal9
2791 Dump all docs prior to 3.0.6 release. Various minor changes to faq and user
2794 Revision 2.23 2006/10/21 22:19:52 hal9
2795 Two new FAQs, a rewrite or two, and some touch ups.
2797 Revision 2.22 2006/10/14 20:33:10 hal9
2798 Three new FAQ's re: templates and blocking, and various minor touch-ups/improvements.
2800 Revision 2.21 2006/10/03 14:40:51 fabiankeil
2801 Added links from the Tor faq to the
2802 configuration chapter in the User Manual.
2804 Revision 2.20 2006/09/26 10:12:37 fabiankeil
2807 Revision 2.19 2006/09/22 10:54:32 hal9
2808 Change references to 3.0.4 to 3.0.5 and minor adjustments.
2810 Revision 2.18 2006/09/22 01:27:55 hal9
2811 Final commit of probably various minor changes here and there. Unless
2812 something changes this should be ready for pending release.
2814 Revision 2.17 2006/09/17 14:56:32 hal9
2815 This includes yet several more new FAQs, some improved wording, enhanced
2816 mark-up, various hyper links to wikipedia to explain key terminology to the
2817 uninitiated, etc. This is ready for release IMO pending final tagging of cvs
2818 and Privoxy version stamping.
2820 Revision 2.16 2006/09/10 15:30:46 hal9
2823 Revision 2.15 2006/09/08 23:05:07 hal9
2824 Fix broken links. Add faq on hosts files. Move most of new windows service
2825 feature to user manual and reference in faq. Various other small changes.
2827 Revision 2.14 2006/09/05 13:25:12 david__schmidt
2828 Add Windows service invocation stuff (duplicated) in FAQ and in user manual under Windows startup. One probably ought to reference the other.
2830 Revision 2.13 2006/09/04 19:20:33 fabiankeil
2831 Adjusted anonymity related sections to match reality.
2832 Added a section about using Privoxy with Tor.
2834 Revision 2.12 2006/09/03 14:15:30 hal9
2835 Various updates, including 7 or 8 new FAQs, and updates/changes to various
2836 other ones to better reflect improvements, additions and changes for the
2837 upcoming release. This is close to final form for 3.0.4 IMHO.
2839 Revision 2.11 2006/07/18 14:48:50 david__schmidt
2840 Reorganizing the repository: swapping out what was HEAD (the old 3.1 branch)
2841 with what was really the latest development (the v_3_0_branch branch)
2843 Revision 1.61.2.41 2004/04/05 13:44:05 oes
2844 Fixed allow-all-cookies alias name; closes SR #929746
2846 Revision 1.61.2.40 2004/01/30 17:00:33 oes
2847 Added OSX Panther problem
2849 Revision 1.61.2.39 2004/01/29 22:53:08 hal9
2850 Minor changes for exempting docs of text/plain. Change copyright date.
2852 Revision 1.61.2.38 2003/12/10 03:39:45 hal9
2853 Added FAQs for: demoronizer, related problems and why its included. Also,
2854 port 8118 already in use questions, and PrivoxyWindowOpen() questions. All in
2855 troubleshooting section.
2857 Revision 1.61.2.37 2003/10/17 11:01:50 oes
2858 Added Q&A for "not being used" page problem
2860 Revision 1.61.2.36 2003/06/26 23:49:20 hal9
2861 More on the filter/source code problem.
2863 Revision 1.61.2.35 2003/06/26 13:38:08 hal9
2864 Add FAQ on whether configuring Privoxy is necessary or not.
2866 Revision 1.61.2.34 2003/06/26 03:00:03 hal9
2867 Sorry, found another copyright date.
2869 Revision 1.61.2.33 2003/06/26 02:57:05 hal9
2870 Fix typo (finally!) and very minor modifications.
2872 Revision 1.61.2.32 2003/06/26 02:52:04 hal9
2875 Revision 1.61.2.31 2003/06/25 01:27:51 hal9
2876 Fix copyright, and a few nits.
2878 Revision 1.61.2.30 2003/06/25 01:13:52 hal9
2881 - FAQ on "Unable to get my own hostname"
2882 - Another one on filtering effects on text files.
2884 Revision 1.61.2.29 2003/06/15 21:32:58 hal9
2885 Add to the 4.17 (filtering effects on downloaded files).
2887 Revision 1.61.2.28 2003/03/18 19:37:21 oes
2888 s/Advanced|Radical/Adventuresome/g to avoid complaints re fun filter
2890 Revision 1.61.2.27 2002/12/01 06:31:58 hal9
2891 Add faq on win32 error 503 due to ZoneAlarm.
2893 Revision 1.61.2.26 2002/11/17 06:41:06 hal9
2894 Move default profiles table from FAQ to U-M, and other minor related changes.
2897 Revision 1.61.2.25 2002/10/29 03:21:50 hal9
2898 Add 3 Q/A's relating to HTML in email. Other minor touchups.
2900 Revision 1.61.2.24 2002/10/15 12:50:22 oes
2901 s/Advanced/Radical/ (stupid me)
2903 Revision 1.61.2.23 2002/10/15 12:38:56 oes
2904 Added Microsuck faq; more detail for PHP problem
2906 Revision 1.61.2.22 2002/10/12 01:13:13 hal9
2907 Updates for demoronizer, more commentary on Radical profile, and update on
2908 the srvany.exe/icon fix.
2910 Revision 1.61.2.21 2002/10/10 04:09:35 hal9
2911 s/Advanced/Radical/ and added very brief note.
2913 Revision 1.61.2.20 2002/09/26 01:22:45 hal9
2914 Small additions for LAN setup, content-cookies/SSL, and FTP non-support.
2916 Revision 1.61.2.19 2002/08/25 23:31:56 hal9
2917 Fix one grammatical error. Add brief FAQ relating to tranparent proxies (ie
2918 port 80 setting). Add FAQ on effects of Privoxy on downloaded files
2919 (especially filtering).
2921 Revision 1.61.2.18 2002/08/14 16:39:37 hal9
2922 Fix wrong tag on FAQ addition.
2924 Revision 1.61.2.17 2002/08/14 00:01:18 hal9
2927 Revision 1.61.2.16 2002/08/13 00:10:38 hal9
2928 Add faq to troubleshooting re: blank page syndrome, ie {-prevent-compression}.
2930 Revision 1.61.2.15 2002/08/10 11:34:22 oes
2931 Add disclaimer about probably being out-of-date
2933 Revision 1.61.2.14 2002/08/07 02:53:43 hal9
2934 Fix some minor markup errors, and move one OSX Q/A to troubleshooting section.
2936 Revision 1.61.2.13 2002/08/06 11:55:32 oes
2937 Added missing close tag
2939 Revision 1.61.2.12 2002/08/06 11:43:46 david__schmidt
2940 Updated OSX uninstall FAQ... we have an uninstall script now.
2942 Revision 1.61.2.11 2002/08/06 08:54:03 oes
2943 Style police: Fixed formatting details
2945 Revision 1.61.2.10 2002/08/02 14:00:25 david__schmidt
2946 Made the OSX removal commands far less dangerous
2948 Revision 1.61.2.9 2002/08/02 13:14:45 oes
2949 Added warning about sudo rm -r for Mac OSX deinstallation; moved this item to install section
2951 Revision 1.61.2.8 2002/08/02 02:01:42 david__schmidt
2952 Add FAQ item for MSIE on OSX HTTP proxy confusion
2954 Revision 1.61.2.7 2002/08/02 01:46:01 david__schmidt
2955 Added FAQ item for Mac OSX uninstall woes
2957 Revision 1.61.2.6 2002/07/30 20:04:56 hal9
2958 Fix typo: 'schould'.
2960 Revision 1.61.2.5 2002/07/26 15:22:58 oes
2961 - Updated to reflect changes in standard.action
2962 - Added info on where to get updated actions files
2964 Revision 1.61.2.4 2002/07/25 21:42:29 hal9
2965 Add brief notes on not proxying non-HTTP protocols.
2967 Revision 1.61.2.3 2002/06/09 16:36:33 hal9
2968 Clarifications on filtering and MIME. Hardcode 'latest release' in index.html.
2970 Revision 1.61.2.2 2002/06/06 02:51:34 hal9
2971 Fix typo in URL http:/config.privoxy.org
2973 Revision 1.61.2.1 2002/06/05 23:10:43 hal9
2974 Add new FAQ re: DUN/IE. Change release date from May to June :)
2976 Revision 1.61 2002/05/25 12:37:25 hal9
2977 Various minor changes and edits.
2979 Revision 1.60 2002/05/22 17:17:48 oes
2980 Proofread & added more links into u-m
2982 Revision 1.59 2002/05/15 04:03:30 hal9
2983 Fix ulink -> link markup.
2985 Revision 1.58 2002/05/10 01:48:20 hal9
2986 This is mostly proposed copyright/licensing additions and changes. Docs
2987 are still GPL, but licensing and copyright are more visible. Also, copyright
2988 changed in doc header comments (eliminate references to JB except FAQ).
2990 Revision 1.57 2002/05/05 20:26:02 hal9
2991 Sorting out license vs copyright in these docs.
2993 Revision 1.56 2002/05/04 08:44:44 swa
2996 Revision 1.55 2002/05/04 00:41:56 hal9
2997 -Remove TOC/first page kludge in favor of proper handling via dsl file.
2999 Revision 1.54 2002/05/03 05:06:44 hal9
3000 Add brief Q/A on transparent proxies.
3002 Revision 1.53 2002/05/03 01:34:52 hal9
3003 Fix section numbering for new sections (due to TOC kludge).
3005 Revision 1.52 2002/04/29 03:08:43 hal9
3006 -Added new Q/A on new actions file set up (pointer to u-m)
3007 -Fixed a few broken links and converted old actions as a result of
3010 Revision 1.51 2002/04/26 17:24:31 swa
3011 bookmarks cleaned, changed structure of user manual, screen and programlisting cleanups, and numerous other changes that I forgot
3013 Revision 1.50 2002/04/26 05:25:23 hal9
3014 Mass commit to catch a few scattered fixes.
3016 Revision 1.49 2002/04/12 10:10:18 swa
3019 Revision 1.48 2002/04/10 18:45:15 swa
3022 Revision 1.47 2002/04/10 04:05:32 hal9
3025 Revision 1.45 2002/04/08 22:59:26 hal9
3026 Version update. Spell chkconfig correctly :)
3028 Revision 1.44 2002/04/07 21:24:29 hal9
3029 Touch up on name change.
3031 Revision 1.43 2002/04/04 21:59:53 hal9
3032 Added NT/W2K service/icon situation.
3034 Revision 1.42 2002/04/04 18:46:47 swa
3035 consistent look. reuse of copyright, history et. al.
3037 Revision 1.41 2002/04/04 06:48:37 hal9
3038 Structural changes to allow for conditional inclusion/exclusion of content
3039 based on entity toggles, e.g. 'entity % p-not-stable "INCLUDE"'. And
3040 definition of internal entities, e.g. 'entity p-version "2.9.13"' that will
3041 eventually be set by Makefile.
3042 More boilerplate text for use across multiple docs.
3044 Revision 1.40 2002/04/03 04:22:03 hal9
3045 Fixed several typos.
3047 Revision 1.39 2002/04/03 03:53:03 hal9
3048 Revert some changes, and then make some news, to layout, and appearance.
3050 Revision 1.38 2002/04/02 03:49:10 hal9
3051 Major changes to doc structure and layout. Sections are not automatically
3052 numbered now. TOC is on page by itself.
3054 Revision 1.37 2002/04/01 16:24:07 hal9
3055 -Rework of supported Q/A.
3056 -Set up entities to include boilerplate text.
3058 Revision 1.36 2002/03/31 23:18:47 hal9
3059 More on dealing with BLOCKED.
3061 Revision 1.35 2002/03/30 04:14:19 hal9
3062 Fix privoxy.org/config links.
3064 Revision 1.34 2002/03/29 04:35:56 hal9
3067 Revision 1.33 2002/03/29 01:31:48 hal9
3068 Several new Q/A's and other touch ups.
3070 Revision 1.32 2002/03/27 00:57:03 hal9
3071 Touch ups for name change.
3073 Revision 1.31 2002/03/26 22:29:55 swa
3074 we have a new homepage!
3076 Revision 1.30 2002/03/25 16:39:22 hal9
3077 A few new sections. Made all links relative to user-manual.
3079 Revision 1.29 2002/03/25 05:23:57 hal9
3080 Moved section, and touch ups.
3082 Revision 1.28 2002/03/25 04:27:33 hal9
3083 New section related to name change.
3085 Revision 1.25 2002/03/24 16:08:08 swa
3086 we are too lazy to make a block-built
3087 privoxy logo. hence removed the option.
3089 Revision 1.24 2002/03/24 15:46:20 swa
3090 name change related issue.
3092 Revision 1.23 2002/03/24 12:33:01 swa
3095 Revision 1.22 2002/03/24 11:51:00 swa
3096 name change. changed filenames.
3098 Revision 1.21 2002/03/24 11:01:06 swa
3101 Revision 1.20 2002/03/23 15:13:11 swa
3102 renamed every reference to the old name with foobar.
3103 fixed "application foobar application" tag, fixed
3104 "the foobar" with "foobar". left junkbustser in cvs
3105 comments and remarks to history untouched.
3107 Revision 1.19 2002/03/21 17:01:54 hal9
3110 Revision 1.18 2002/03/18 16:40:31 hal9
3113 Revision 1.17 2002/03/18 03:53:53 hal9
3116 Revision 1.16 2002/03/17 21:32:56 hal9
3117 A few more additions.
3119 Revision 1.15 2002/03/17 07:25:59 hal9
3120 Correcting some of my typos, and some additions.
3122 Revision 1.14 2002/03/17 02:39:13 hal9
3123 A little more added ...
3125 Revision 1.13 2002/03/17 00:22:20 hal9
3126 Adding new stuff, and trying to incorporate stuff from old faq.
3128 Revision 1.12 2002/03/11 20:13:21 swa
3131 Revision 1.11 2002/03/11 18:42:27 swa
3134 Revision 1.10 2002/03/11 13:13:27 swa
3135 correct feedback channels
3137 Revision 1.9 2002/03/10 23:34:04 swa
3138 more info on not hiding ip address
3140 Revision 1.8 2002/03/09 15:55:48 swa
3141 added default config section
3143 Revision 1.7 2002/03/07 18:16:55 swa
3146 Revision 1.6 2002/03/07 13:16:31 oes
3147 Committing changes by Stefan
3149 Revision 1.5 2002/03/02 15:50:04 swa
3150 2.9.11 version. more input for docs.
3152 Revision 1.4 2002/02/24 14:34:24 jongfoster
3153 Formatting changes. Now changing the doctype to DocBook XML 4.1
3154 will work - no other changes are needed.
3156 Revision 1.3 2001/09/23 10:13:48 swa
3157 upload process established. run make webserver and
3158 the documentation is moved to the webserver. documents
3159 are now linked correctly.
3161 Revision 1.2 2001/09/13 15:20:17 swa
3162 merged standards into developer manual
3164 Revision 1.1 2001/09/12 15:36:41 swa
3165 source files for junkbuster documentation
3167 Revision 1.3 2001/09/10 17:43:59 swa
3168 first proposal of a structure.
3170 Revision 1.2 2001/06/13 14:28:31 swa
3171 docs should have an author.
3173 Revision 1.1 2001/06/13 14:20:37 swa
3174 first import of project's documentation for the webserver.