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 "UNRELEASED">
13 <!entity % p-not-stable "INCLUDE">
14 <!entity % p-stable "IGNORE">
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 2.28 2007/10/27 15:14:16 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 2.28 2007/10/27 15:14:16 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>, <application>Opera</application>, and
522 <application>Safari</application> among others.
523 Direct browser support is not an absolute requirement since
524 <application>Privoxy</application> runs as a separate application and talks
525 to the browser in the standardized HTTP protocol, just like a web server
530 <sect2 renderas="sect3" id="whichos">
531 <title>Which operating systems are supported?</title>
533 Include supported.sgml here:
538 <sect2 renderas="sect3" id="email-client">
539 <title>Can I use Privoxy with my email client?</title>
541 As long as there is some way to set a HTTP proxy for the client, then yes,
542 any application can be used, whether it is strictly speaking a
543 <quote>browser</quote> or not. Though this may not be the best approach for
544 dealing with some of the common abuses of HTML in email. See <link
545 linkend="outlook">How can I configure <application>Privoxy</application>
546 with <application>Outlook Express</application>?</link> below for more on
550 Be aware that HTML email presents a number of unique security and privacy
551 related issues, that can require advanced skills to overcome. The developers
552 recommend using email clients that can be configured to convert HTML to plain
553 text for these reasons.
557 <!-- Nobody is going to still be doing this!
558 <sect2 renderas="sect3" id="newinstall"><title>Can I install
559 Privoxy over Junkbuster?</title>
561 We recommend you un-install <application>Junkbuster</application>
562 first to minimize conflicts and confusion. You may want to
563 save your old configuration files for future reference. The configuration
564 files and syntax have substantially changed, so you will need to manually
565 port your old patterns. See the <ulink url="../user-manual/upgradersnote.html">note
566 to upgraders</ulink> and <ulink url="../user-manual/installation.html">installation
567 chapter</ulink> in the <ulink url="../user-manual/index.html">User Manual</ulink>
571 Note: Some installers may automatically un-install
572 <application>Junkbuster</application>, if present!
578 <sect2 renderas="sect3" id="firststep">
579 <title>I just installed Privoxy. Is there anything
580 special I have to do now?</title>
583 All browsers must be told to use <application>Privoxy</application>
584 as a proxy by specifying the correct proxy address and port number
585 in the appropriate configuration area for the browser. See
586 <ulink url="../user-manual/startup.html">the User Manual for more
587 details</ulink>. You should also flush your browser's memory and disk cache to get rid of any
588 cached junk items, and remove any stored
589 <ulink url="http://en.wikipedia.org/wiki/Browser_cookie">cookies</ulink>.
595 <sect2 renderas="sect3" id="localhost"><title>What is the proxy address of Privoxy?</title>
597 If you set up the <application>Privoxy</application> to run on
598 the computer you browse from (rather than your ISP's server or some
599 networked computer on a LAN), the proxy will be on <literal>127.0.0.1</literal>
600 (sometimes referred to as <quote>localhost</quote>,
601 which is the special name used by every computer on the Internet to refer
602 to itself) and the port will be 8118 (unless you have <application>Privoxy</application>
603 to run on a different port with the <ulink
604 url="../user-manual/config.html#LISTEN-ADDRESS">listen-address</ulink> config option).
607 When configuring your browser's proxy settings you typically enter
608 the word <quote>localhost</quote> or the IP address <quote>127.0.0.1</quote>
609 in the boxes next to <quote>HTTP</quote> and <quote>Secure</quote> (HTTPS) and
610 then the number <quote>8118</quote> for <quote>port</quote>.
611 This tells your browser to send all web requests to <application>Privoxy</application>
612 instead of directly to the Internet.
615 <application>Privoxy</application> can also be used to proxy for
616 a Local Area Network. In this case, your would enter either the IP
617 address of the LAN host where <application>Privoxy</application>
618 is running, or the equivalent hostname, e.g. <literal>192.168.1.1</literal>.
619 Port assignment would be same as above. Note that
620 <application>Privoxy</application> doesn't listen on any LAN interfaces by
624 <application>Privoxy</application> does not currently handle
625 any other protocols such as FTP, SMTP, IM, IRC, ICQ, etc. Be sure that
626 proxying any of these other protocols is not activated.
630 <sect2 renderas="sect3" id="nothing">
631 <title>I just installed Privoxy, and nothing is happening.
632 All the ads are there. What's wrong?</title>
635 Did you configure your browser to use <application>Privoxy</application>
636 as a proxy? It does not sound like it. See above. You might also try flushing
637 the browser's caches to force a full re-reading of pages. You can verify
638 that <application>Privoxy</application> is running, and your browser
639 is correctly configured by entering the special URL:
640 <ulink url="http://p.p/">http://p.p/</ulink>.
641 <!-- Use http://p.p/ instead of http://config.privoxy.org/ here because
642 of potential redirect caching problem (see next Q). -->
643 This should take you to a page titled <quote>This is Privoxy..</quote> with
644 access to <application>Privoxy's</application> internal configuration.
645 If you see this, then you are good to go. If you receive a page saying
646 <quote>Privoxy is not running</quote>, then the browser is not set up to use
647 your <application>Privoxy</application> installation.
648 If you receive anything else (probably nothing at all), it could either
649 be that the browser is not set up correctly, or that
650 <application>Privoxy</application> is not running at all. Check the <ulink
651 url="../user-manual/config.html#LOGFILE">log file</ulink>. For instructions
652 on starting <application>Privoxy</application> and browser configuration,
653 see the <ulink url="http://www.privoxy.org/user-manual/startup.html">chapter
654 on starting <application>Privoxy</application></ulink> in the
655 <ulink url="http://www.privoxy.org/user-manual/">User Manual</ulink>.
660 <sect2 renderas="sect3" id="notused">
661 <title>I get a <quote>Privoxy is not being used</quote> dummy page although
662 Privoxy is running and being used.</title>
665 First, make sure that Privoxy is <emphasis>really</emphasis> running and
666 being used by visiting <ulink url="http://p.p/">http://p.p/</ulink>. You
667 should see the <application>Privoxy</application> main page. If not, see
668 the <ulink url="http://www.privoxy.org/user-manual/startup.html">chapter
669 on starting <application>Privoxy</application></ulink> in the
670 <ulink url="http://www.privoxy.org/user-manual/">User Manual</ulink>.
674 Now if <ulink url="http://p.p/">http://p.p/</ulink> works for you, but
675 other parts of <application>Privoxy</application>'s web interface show
676 the dummy page, your browser has cached a redirection it encountered before
677 <application>Privoxy</application> was being used. You need to clear your
678 browser's cache. Note that shift-reloading the dummy page won't help, since
679 that'll only refresh the dummy page, not the redirection that lead you there.
683 The procedure for clearing the cache varies from browser to browser. For
684 example, <application>Mozilla/Netscape</application> users would click
685 <guibutton>Edit</guibutton> --> <guibutton>Preferences</guibutton> -->
686 <guibutton>Advanced</guibutton> --> <guibutton>Cache</guibutton> and
687 then click both <quote><guibutton>Clear Memory Cache</guibutton></quote>
688 and <quote><guibutton>Clear Disk Cache</guibutton></quote>.
689 And, <application>Firefox</application> users would click
690 <guibutton>Tools</guibutton> --> <guibutton>Options</guibutton> -->
691 <guibutton>Privacy</guibutton> --> <guibutton>Cache</guibutton> and
692 then click <quote><guibutton>Clear Cache Now</guibutton></quote>.
700 <!-- ~~~~~ New section ~~~~~ -->
702 <sect1 id="configuration"><title>Configuration</title>
703 <sect2 renderas="sect3">
704 <title id="actionsfile">What exactly is an <quote>actions</quote> file?</title>
707 &my-app; utilizes the concept of <quote>
708 <ulink url="../user-manual/actions-file.html#ACTIONS">actions</ulink></quote>
709 that are used to manipulate and control web page data.
710 <ulink url="../user-manual/actions-file.html">Actions files</ulink>
711 are where these <ulink url="../user-manual/actions-file.html#ACTIONS">actions</ulink>
712 that <application>Privoxy</application> could take while processing a certain
713 request, are configured. Typically, you would define a set of default actions
714 that apply globally to all URLs, then add exceptions to these defaults where needed.
715 There is a wide array of actions available that give the user a high degree
716 of control and flexibility on how to process each and every web page.
720 Actions can be defined on a <ulink
721 url="../user-manual/actions-file.html#AF-PATTERNS">URL pattern</ulink> basis, i.e.
722 for single URLs, whole web sites, groups or parts thereof etc. Actions can also be
723 grouped together and then applied to requests matching one or more patterns.
724 There are many possible actions that might apply to any given site. As an example,
725 if you are blocking <ulink url="http://en.wikipedia.org/wiki/Browser_cookie">cookies</ulink>
726 as one of your default actions, but need to accept cookies from a given site,
727 you would need to define an exception for this site in one of your actions
728 files, preferably in <filename>user.action</filename>.
733 <sect2 renderas="sect3" id="actionss">
734 <title>The <quote>actions</quote> concept confuses me. Please list
735 some of these <quote>actions</quote>.</title>
737 For a comprehensive discussion of the actions concept, please refer
738 to the <ulink url="../user-manual/actions-file.html">actions file
739 chapter</ulink> in the <ulink url="../user-manual/index.html">User
740 Manual</ulink>. It includes a <ulink
741 url="../user-manual/actions-file.html#ACTIONS">list of all actions</ulink>
742 and an <ulink url="../user-manual/actions-file.html#ACT-EXAMPLES">actions
743 file tutorial</ulink> to get you started.
748 <sect2 renderas="sect3">
749 <title id="actconfig">How are actions files configured? What is the easiest
750 way to do this?</title>
753 Actions files are just text files in a special syntax and can be edited
754 with a text editor. But probably the easiest way is to access
755 <application>Privoxy</application>'s user interface with your web browser
756 at <ulink url="http://config.privoxy.org/">http://config.privoxy.org/</ulink>
757 (Shortcut: <ulink url="http://p.p/">http://p.p/</ulink>) and then select
758 <quote><ulink url="http://config.privoxy.org/show-status">View &
759 change the current configuration</ulink></quote> from the menu.
764 <sect2 renderas="sect3">
765 <title>There are several different <quote>actions</quote> files. What are
766 the differences?</title>
769 are being included by the developers, to be used for
770 different purposes: These are
771 <filename>default.action</filename>, the <quote>main</quote> actions file
772 which is actively maintained by the <application>Privoxy</application>
773 developers and typically sets the default policies, <filename>user.action</filename>, where users are encouraged
774 to make their private customizations, and <filename>standard.action</filename>,
775 which is for internal <application>Privoxy</application> use only.
776 Please see <ulink url="../user-manual/actions-file.html">the actions chapter</ulink>
777 in the <ulink url="../user-manual/index.html">User Manual</ulink> for a more
778 detailed explanation.
782 Earlier versions included three different versions of the
783 <filename>default.action</filename> file. The new scheme allows for
784 greater flexibility of local configuration, and for browser based
785 selection of pre-defined <quote>aggressiveness</quote> levels.
790 <sect2 renderas="sect3" id="getupdates"><title>Where can I get updated Actions Files?</title>
792 Based on your feedback and the continuing development, updates of
793 <filename>default.action</filename> will be
794 made available from time to time on the <ulink
795 url="http://sourceforge.net/project/showfiles.php?group_id=11118">files section</ulink> of
796 our <ulink url="http://sf.net/projects/ijbswa/">project page</ulink>.
800 If you wish to receive an email notification whenever we release updates of
801 <application>Privoxy</application> or the actions file, <ulink
802 url="http://lists.sourceforge.net/lists/listinfo/ijbswa-announce/">subscribe
803 to our announce mailing list</ulink>, ijbswa-announce@lists.sourceforge.net.
808 <sect2 renderas="sect3" id="newconfig"><title>Can I use my old config files?</title>
810 The syntax and purpose of configuration files has remained roughly the
811 same throughout the 3.x series, but backwards compatibility is not guaranteed.
812 Also each release contains updated, <quote>improved</quote> versions and it is
813 therefore strongly recommended to use the newer configuration files.
817 <sect2 renderas="sect3" id="difficult">
818 <title>Why is the configuration so complicated?</title>
820 <quote>Complicated</quote> is in the eye of the beholder. Those that are
821 familiar with some of the underlying concepts, such as regular expression
822 syntax, take to it like a fish takes to water. Also, software that tries
823 hard to be <quote>user friendly</quote>, often lacks sophistication and
824 flexibility. There is always that trade-off there between power vs.
825 easy-of-use. Furthermore, anyone is welcome to contribute ideas and
826 implementations to enhance &my-app;.
830 <sect2 renderas="sect3" id="yahoo"><title>How can I make my Yahoo/Hotmail/Gmail account work?</title>
832 The default configuration shouldn't impact the usability of any of these services.
833 It may, however, make all <ulink
834 url="http://en.wikipedia.org/wiki/Browser_cookie">cookies</ulink>
835 temporary, so that your browser will forget your
836 login credentials in between browser sessions. If you would like not to have to log
837 in manually each time you access those websites, simply turn off all cookie handling
838 for them in the <filename>user.action</filename> file. An example for yahoo might
842 <screen># Allow all cookies for Yahoo login:
844 { -<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> }
845 .login.yahoo.com</screen>
848 These kinds of sites are often quite complex and heavy with
849 <ulink url="http://en.wikipedia.org/wiki/Javascript">Javascript</ulink> and
850 thus <quote>fragile</quote>. So if <emphasis>still</emphasis> a problem,
852 url="../user-manual/actions-file.html#ALIASES">alias</ulink> just for such
856 <screen># Gmail is a _fragile_ site:
858 { <literal>fragile</literal> }
860 mail.google.com</screen>
863 Be sure to flush your browser's caches whenever making these kinds of
864 changes, just to make sure the changes <quote>take</quote>.
867 Make sure the domain, host and path are appropriate as well. Your browser can
868 tell you where you are specifically and you should use that information for
869 your configuration settings. Note that above it is not referenced as
870 <literal>gmail.com</literal>, which is a valid domain name.
875 <sect2 renderas="sect3" id="configfiles"> <title>What's the difference between the
876 <quote>Cautious</quote>, <quote>Medium</quote> and <quote>Advanced</quote> defaults?</title>
878 Configuring <application>Privoxy</application> is not entirely trivial. To
879 help you get started, we provide you with three different default action
880 <quote>profiles</quote> in the web based actions file editor at <ulink
881 url="http://config.privoxy.org/show-status">http://config.privoxy.org/show-status</ulink>.
882 See the <ulink url="../user-manual/actions-file.html"><citetitle>User
883 Manual</citetitle></ulink> for a list of actions, and how the default
888 Where the defaults are likely to break some sites, exceptions for
889 known popular <quote>problem</quote> sites are included, but in
890 general, the more aggressive your default settings are, the more exceptions
891 you will have to make later. New users are best to start off in
892 <quote>Cautious</quote> setting. This is safest and will have the fewest
893 problems. See the <ulink
894 url="../user-manual/index.html"><citetitle>User Manual</citetitle></ulink>
895 for a more detailed discussion.
899 It should be noted that the <quote>Advanced</quote> profile (formerly known
900 as the <quote>Adventuresome</quote> profile) is more
901 aggressive, and will make use of some of
902 <application>Privoxy's</application> advanced features. Use at your own risk!
907 <sect2 renderas="sect3" id="browseconfig"> <title>Why can I change the configuration
908 with a browser? Does that not raise security issues?</title>
910 It may seem strange that regular users can edit the config files with their
911 browsers, although the whole <filename>/etc/privoxy</filename> hierarchy
912 belongs to the user <quote>privoxy</quote>, with only 644 permissions.
915 When you use the browser-based editor, <application>Privoxy</application>
916 itself is writing to the config files. Because
917 <application>Privoxy</application> is running as the user <quote>privoxy</quote>,
918 it can update its own config files.
921 If you run <application>Privoxy</application> for multiple untrusted users (e.g. in
922 a LAN), you will probably want to make sure that the turn the web-based
923 editor and remote toggle features are <quote>off</quote> by setting <quote><literal><ulink
924 url="../user-manual/config.html#ENABLE-EDIT-ACTIONS">enable-edit-actions</ulink>
925 0</literal></quote> and <quote><literal><ulink
926 url="../user-manual/config.html#ENABLE-REMOTE-TOGGLE">enable-remote-toggle</ulink>
927 0</literal></quote> in the <ulink url="../user-manual/config.html">main configuration file</ulink>.
930 Note that in the default configuration, only local users (i.e. those on
931 <quote>localhost</quote>) can connect to <application>Privoxy</application>,
932 so this is (normally) not a security problem.
937 <sect2 renderas="sect3">
938 <title id="filterfile">What is the <filename>default.filter</filename> file? What is a <quote>filter</quote>?</title>
940 The <ulink url="../user-manual/filter-file.html"><filename>default.filter</filename></ulink>
941 file is where <emphasis>filters</emphasis> as supplied by the developers are defined.
942 Filters are a special subset of actions that can be used to modify or
943 remove, web page content on the fly. Filters apply to <emphasis>anything</emphasis>
944 in the page source (and optionally both client and server headers), including
945 HTML tags, and JavaScript. Regular expressions are used to accomplish this.
946 There are a number of pre-defined filters to deal with common annoyances. The
947 filters are only defined here, to invoke them, you need to use the
949 url="../user-manual/actions-file.html#FILTER"><literal>filter</literal>
950 action</ulink> in one of the actions files. Filtering is automatically
951 disabled for inappropriate MIME types.
955 If you are familiar with regular expressions, and HTML, you can look at
956 the provided <filename>default.filter</filename> with a text editor and define
957 your own filters. This is potentially a very powerful feature, but
958 requires some expertise in both regular expressions and HTML/HTTP.
959 <![%p-newstuff;[ You should
960 place any modifications to the default filters, or any new ones you create
961 in a separate file, such as <filename>user.filter</filename>, so they won't
962 be overwritten during upgrades.
963 The ability to define multiple filter files
964 in <filename>config</filename> is a new feature as of v. 3.0.5.]]>
968 There is no GUI editor option for this part of the configuration,
969 but you can disable/enable the various pre-defined filters of the included
970 <filename>default.filter</filename> file with the <ulink
971 url="http://config.privoxy.org/show-status">web-based actions file editor</ulink>.
976 <sect2 renderas="sect3" id="lanconfig">
977 <title>How can I set up Privoxy to act as a proxy for my
980 By default, <application>Privoxy</application> only responds to requests
981 from <literal>127.0.0.1</literal> (localhost). To have it act as a server for
982 a network, this needs to be changed in the <ulink
983 url="../user-manual/config.html">main configuration file</ulink>. Look for
985 url="../user-manual/config.html#LISTEN-ADDRESS">listen-address</ulink></literal>
986 option, which may be commented out with a <quote>#</quote> symbol. Make sure
987 it is uncommented, and assign it the address of the LAN gateway interface,
988 and port number to use. Assuming your LAN address is 192.168.1.1 and you
989 wish to run <application>Privoxy</application> on port 8118, this line
995 listen-address 192.168.1.1:8118</screen>
999 Save the file, and restart <application>Privoxy</application>. Configure
1000 all browsers on the network then to use this address and port number.
1004 Alternately, you can have <application>Privoxy</application> listen on
1005 all available interfaces:
1010 listen-address :8118</screen>
1014 And then use <application>Privoxy's</application>
1016 url="../user-manual/config.html#PERMIT-ACCESS">permit-access</ulink>
1017 feature to limit connections. A firewall in this situation is recommended
1022 The above steps should be the same for any TCP network, regardless of
1027 If you run <application>Privoxy</application> on a LAN with untrusted users,
1028 we recommend that you double-check the <ulink
1029 url="../user-manual/config.html#ACCESS-CONTROL">access control and security</ulink>
1036 <sect2 renderas="sect3">
1037 <title id="noseeum">Instead of ads, now I get a checkerboard pattern. I don't want to see anything.</title>
1039 The replacement for blocked images can be controlled with the <ulink
1040 url="../user-manual/actions-file.html#SET-IMAGE-BLOCKER"><literal>set-image-blocker</literal>
1041 action</ulink>. You have the choice of a checkerboard pattern, a transparent 1x1 GIF
1042 image (aka <quote>blank</quote>), or a redirect to a custom image of your choice.
1043 Note that this choice only has effect for images which are blocked as images, i.e.
1044 whose URLs match both a <literal><ulink
1045 url="../user-manual/actions-file.html#HANDLE-AS-IMAGE">handle-as-image</ulink></literal>
1046 <emphasis>and</emphasis> <literal><ulink
1047 url="../user-manual/actions-file.html#BLOCK">block</ulink></literal> action.
1050 If you want to see nothing, then change the <ulink
1051 url="../user-manual/actions-file.html#SET-IMAGE-BLOCKER"><literal>set-image-blocker</literal>
1052 action</ulink> to <quote>blank</quote>. This can be done by editing the
1053 <filename>user.action</filename> file, or through the <ulink
1054 url="http://config.privoxy.org/show-status">web-based actions file editor</ulink>.
1059 <sect2 renderas="sect3">
1060 <title id="whyseeum">Why would anybody want to see a checkerboard pattern?</title>
1062 Remember that <link linkend="whatsanad">telling which image is an ad and which
1063 isn't</link>, is an educated guess. While we hope that the standard configuration
1064 is rather smart, it will make occasional mistakes. The checkerboard image is visually
1065 decent, and it shows you where images have been blocked, which can be very
1066 helpful in case some navigation aid or otherwise innocent image was
1067 erroneously blocked. It is recommended for new users so they can
1068 <quote>see</quote> what is happening. Some people might also enjoy seeing how
1069 many banners they <emphasis>don't</emphasis> have to see.
1074 <sect2 renderas="sect3">
1075 <title id="blockedbytext">I see some images being replaced with text
1076 instead of the checkerboard image. Why and how do I get rid of this?</title>
1078 This happens when the banners are not embedded in the HTML code of the
1079 page itself, but in separate HTML (sub)documents that are loaded into (i)frames
1080 or (i)layers, and these external HTML documents are blocked. Being non-images
1081 they get replaced by a substitute HTML page rather than a substitute image,
1082 which wouldn't work out technically, since the browser expects and accepts
1083 only HTML when it has requested an HTML document.
1086 The substitute page adapts to the available space and shows itself as a
1087 miniature two-liner if loaded into small frames, or full-blown with a
1088 large red "BLOCKED" banner if space allows.
1091 If you prefer the banners to be blocked by images, you must see to it that
1092 the HTML documents in which they are embedded are not blocked. Clicking
1093 the <quote>See why</quote> link offered in the substitute page will show
1094 you which rule blocked the page. After changing the rule and un-blocking
1095 the HTML documents, the browser will try to load the actual banner images
1096 and the usual image blocking will (hopefully!) kick in.
1101 <sect2 renderas="sect3" id="srvany">
1102 <title>Can Privoxy run as a service
1103 on Win2K/NT/XP?</title>
1106 Yes. Version 3.0.5 introduces full <application>Windows</application> service
1107 functionality. See <ulink url="../user-manual/installation.html#installation-pack-win">
1108 the <citetitle>User Manual</citetitle></ulink> for details on how to install and configure
1109 <application>Privoxy</application> as a service.
1112 Earlier ]]>3.x versions could run as a system service using <command>srvany.exe</command>.
1113 See the discussion at <ulink
1114 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>,
1115 for details, and a sample configuration.
1120 <sect2 renderas="sect3" id="otherproxy">
1121 <title>How can I make Privoxy work with other
1122 proxies like Squid or Tor?</title>
1124 This can be done and is often useful to combine the benefits of
1125 <application>Privoxy</application> with those of a another proxy.
1127 url="../user-manual/config.html#FORWARDING">forwarding chapter</ulink>
1128 in the <ulink url="../user-manual/index.html">User Manual</ulink> which
1129 describes how to do this, and the <link linkend="TOR">
1130 How do I use Privoxy together with
1131 Tor</link> section below.
1135 <sect2 renderas="sect3" id="port-80">
1136 <title>Can I just set Privoxy to use port 80
1137 and thus avoid individual browser configuration?</title>
1140 No, its more complicated than that. This only works with special kinds
1141 of proxies known as <quote>intercepting</quote> proxies (see below).
1146 <sect2 renderas="sect3" id="transparent">
1147 <title>Can Privoxy run as a <quote>transparent
1148 </quote> proxy?</title>
1150 The whole idea of Privoxy is to modify client requests
1151 and server responses in all sorts of ways and therefore
1152 it's not a transparent proxy as described in
1153 <ulink url="http://tools.ietf.org/html/rfc2616">RFC 2616</ulink>.
1156 However, some people say <quote>transparent proxy</quote> when they
1157 mean <quote>intercepting proxy</quote>. If you are one of them,
1158 please read the <ulink url="#intercepting">next entry</ulink>.
1163 <sect2 renderas="sect3" id="intercepting">
1164 <title>Can Privoxy run as a <quote>intercepting</quote> proxy?</title>
1166 <application>Privoxy</application> can't intercept traffic itself,
1167 but it can handle requests that where intercepted and redirected
1168 with a packet filter (like <application>PF</application> or
1169 <application>iptables</application>), as long as the <literal>Host</literal>
1173 As the <literal>Host</literal> header is required by HTTP/1.1 and as most
1174 web sites don't work if it isn't set, this limitation shouldn't be a
1178 Please refer to your packet filter's documentation to learn how to
1179 intercept and redirect traffic into <application>Privoxy</application>. Afterward you just have
1180 to configure <application>Privoxy</application> to
1181 <ulink url="../user-manual/config.html#ACCEPT-INTERCEPTED-REQUESTS">accept intercepted requests</ulink>.
1186 <sect2 renderas="sect3" id="outlook">
1187 <title>How can I configure Privoxy for use with Outlook
1190 <application>Outlook Express</application> uses <application>Internet Explorer</application>
1191 components to both render HTML, and fetch any HTTP requests that may be embedded in an HTML email.
1192 So however you have <application>Privoxy</application> configured to work
1193 with IE, this configuration should automatically be shared.
1197 <sect2 renderas="sect3" id="outlook-more">
1198 <title>How can I have separate rules just for HTML mail?</title>
1200 The short answer is, you can't. <application>Privoxy</application> has no way
1201 of knowing which particular application makes a request, so there is no way to
1202 distinguish between web pages and HTML mail.
1203 <application>Privoxy</application> just blindly proxies all requests. In the
1204 case of <application>Outlook Express</application> (see above), OE uses
1205 IE anyway, and there is no way for <application>Privoxy</application> to ever
1206 be able to distinguish between them (nor could any other proxy type application for
1210 For a good discussion of some of the issues involved (including privacy and
1211 security issues), see
1212 <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>.
1216 <sect2 renderas="sect3" id="sneaky-cookies">
1217 <title>I sometimes notice cookies sneaking through. How?</title>
1220 url="http://en.wikipedia.org/wiki/Browser_cookie">Cookies</ulink> can be
1221 set in several ways. The classic method is via the
1222 <literal>Set-Cookie</literal> HTTP header. This is straightforward, and an
1223 easy one to manipulate, such as the &my-app; concept of
1224 <ulink url="../user-manual/actions-file.html#SESSION-COOKIES-ONLY">session-cookies-only</ulink>.
1225 There is also the possibility of using
1226 <ulink url="http://en.wikipedia.org/wiki/Javascript">Javascript</ulink> to
1227 set cookies (&my-app; calls these <literal>content-cookies</literal>). This
1228 is trickier because the syntax can vary widely, and thus requires a certain
1229 amount of guesswork. It is not realistic to catch all of these short of
1230 disabling Javascript, which would break many sites. And lastly, if the
1231 cookies are embedded in a HTTPS/SSL secure session via Javascript, they are beyond
1232 <application>Privoxy's</application> reach.
1235 All in all, &my-app; can help manage cookies in general, can help minimize
1236 the loss of privacy posed by cookies, but can't realistically stop all
1241 <sect2 renderas="sect3" id="evil-cookies">
1242 <title>Are all cookies bad? Why?</title>
1244 No, in fact there are many beneficial uses of
1246 url="http://en.wikipedia.org/wiki/Browser_cookie">cookies</ulink>. Cookies are just a
1247 method that browsers can use to store data between pages, or between browser
1248 sessions. Sometimes there is a good reason for this, and the user's life is a
1249 bit easier as a result. But there is a long history of some websites taking
1250 advantage of this layer of trust, and using the data they glean from you and
1251 your browsing habits for their own purposes, and maybe to your potential
1252 detriment. Such sites are using you and storing their data on your system.
1253 That is why the privacy conscious watch from whom those cookies come, and why
1254 they really <emphasis>need</emphasis> to be there.
1258 <ulink url="http://en.wikipedia.org/wiki/Browser_cookie">Wikipedia cookie
1259 definition</ulink> for more.
1263 <sect2 renderas="sect3" id="allow-cookies">
1264 <title>How can I allow permanent cookies for my trusted sites?</title>
1267 There are several actions that relate to cookies. The default behavior is to
1268 allow only <quote>session cookies</quote>, which means the cookies only last
1269 for the current browser session. This eliminates most kinds of abuse related
1270 to cookies. But there may be cases where you want cookies to last.
1273 To disable all cookie actions, so that cookies are allowed unrestricted,
1274 both in and out, for <literal>example.com</literal>:
1278 { -crunch-incoming-cookies -crunch-outgoing-cookies -session-cookies-only -filter{content-cookies} }
1279 .example.com</screen>
1282 Place the above in <filename>user.action</filename>. Note that some of these may
1283 be off by default anyway, so this might be redundant, but there is no harm
1284 being explicit in what you want to happen. <filename>user.action</filename>
1285 includes an alias for this situation, called
1286 <literal>allow-all-cookies</literal>.
1290 <sect2 renderas="sect3" id="multiples">
1291 <title>Can I have separate configurations for different users?</title>
1293 Each instance of <application>Privoxy</application> has its own
1294 configuration, including such attributes as the TCP port that it listens on.
1295 What you can do is run multiple instances of <application>Privoxy</application>, each with
1297 <ulink url="../user-manual/config.html#LISTEN-ADDRESS">listen-address</ulink>
1298 configuration setting, and configuration path, and then
1299 each of these can have their own configurations. Think of it as per-port
1303 Simple enough for a few users, but for large installations, consider having
1304 groups of users that might share like configurations.
1308 <sect2 renderas="sect3" id="whitelists">
1309 <title>Can I set-up Privoxy as a whitelist of
1310 <quote>good</quote> sites?</title>
1312 Sure. There are a couple of things you can do for simple white-listing.
1313 Here's one real easy one:
1316 ############################################################
1318 ############################################################
1319 { <ulink url="../user-manual/actions-file.html#BLOCK">+block</ulink> }
1320 / # Block *all* URLs
1322 ############################################################
1324 ############################################################
1325 { <ulink url="../user-manual/actions-file.html#BLOCK">-block</ulink> }
1328 games.example.com</screen>
1330 This allows access to only those three sites by first blocking all URLs, and
1331 then subsequently allowing three specific exceptions.
1334 A more interesting approach is <application>Privoxy's</application>
1335 <literal>trustfile</literal> concept, which incorporates the notion of
1336 <quote>trusted referrers</quote>. See the <ulink
1337 url="../user-manual/config.html#TRUSTFILE">User Manual Trust</ulink>
1341 These are fairly simple approaches and are not completely foolproof. There
1342 are various other configuration options that should be disabled (described
1343 elsewhere here and in <ulink url="../user-manual/">the User Manual</ulink>)
1344 so that users can't modify their own configuration and easily circumvent the
1349 <sect2 renderas="sect3" id="no-adblock">
1350 <title>How can I turn off ad-blocking?</title>
1352 Ad blocking is achieved through a complex application of various &my-app;
1353 <ulink url="../user-manual/actions-file.html">actions</ulink>. These
1354 actions are deployed against simple images, banners, flash animations,
1355 text pages, JavaScript, pop-ups and pop-unders, etc., so its not as simple as
1356 just turning one or two actions off. The various actions that make up
1357 &my-app; ad blocking are hard-coded into the default configuration files. It
1358 has been assumed that everyone using &my-app; is interested in this
1362 If you want to do without this, there are several approaches you can take:
1363 You can manually undo the many block rules in
1364 <filename>default.action</filename>. Or even easier, just create your own
1365 <filename>default.action</filename> file from scratch without the many ad
1366 blocking rules, and corresponding exceptions. Or lastly, if you are not
1367 concerned about the additional blocks that are done for privacy reasons, you
1368 can very easily over-ride <emphasis>all</emphasis> blocking with the
1369 following very simple rule in your <filename>user.action</filename>:
1373 # Unblock everybody, everywhere
1374 { <ulink url="../user-manual/actions-file.html#BLOCK">-block</ulink> }
1375 / # UN-Block *all* URLs</screen>
1378 Or even a more comprehensive reversing of various ad related actions:
1382 # Unblock everybody, everywhere, and turn off appropriate filtering, etc
1383 { <ulink url="../user-manual/actions-file.html#BLOCK">-block</ulink> \
1384 <ulink url="../user-manual/actions-file.html#FILTER-BANNERS-BY-SIZE">-filter{banners-by-size}</ulink> \
1385 <ulink url="../user-manual/actions-file.html#FILTER-BANNERS-BY-LINK">-filter{banners-by-link}</ulink> \
1386 <literal>allow-popups</literal> \
1388 / # UN-Block *all* URLs and allow ads</screen>
1391 This last <quote>action</quote> in this compound statement,
1392 <literal>allow-popups</literal>, is an <ulink
1393 url="../user-manual/actions-file.html#ALIASES">alias</ulink> that disables
1394 various pop-up blocking features.
1398 <sect2 renderas="sect3" id="templates">
1399 <title>How can I have custom template pages, like the
1400 <emphasis>BLOCKED</emphasis> page?</title>
1402 &my-app; <quote>templates</quote> are specialized text files utilized by
1403 &my-app; for various purposes and can easily be modified using any text
1404 editor. All the template pages are installed in a sub-directory appropriately
1405 named: <filename>templates</filename>. Knowing something about HTML syntax
1406 will of course be helpful. You cannot rename any of these files, or create
1407 completely new templates, that is not possible. But you can change the page
1408 content to whatever you like. Be forewarned that these files are subject to
1409 being overwritten during upgrades, so be sure to save any customizations.
1413 <sect2 renderas="sect3" id="blockall">
1414 <title>How can I remove the <quote>Go There Anyway</quote> link from
1415 the <emphasis>BLOCKED</emphasis> page?</title>
1417 There is more than one way to do it.
1420 Editing the BLOCKED template page (see above) may dissuade some users, but
1421 this method is easily circumvented. Where you need this level of control, you
1422 should build &my-app; from source, and enable various features that are
1423 available as compile-time options. You should
1424 <command>configure</command> the sources as follows:
1428 ./configure --disable-toggle --disable-editor --disable-force</screen>
1431 This will create an executable with hard-coded security features so that
1432 &my-app; does not allow easy bypassing of blocked sites, or changing the
1433 current configuration via any connected user's web browser.
1436 Note that all of these features can also be toggled on/off via options in
1437 <application>Privoxy's</application> main <ulink
1438 url="../user-manual/config.html#ACCESS-CONTROL">config</ulink> file which
1439 means you don't have to recompile anything.
1445 <!-- ~ End section ~ -->
1448 <!-- ~~~~~ New section ~~~~~ -->
1450 <sect1 id="misc"><title>Miscellaneous</title>
1452 <sect2 renderas="sect3">
1453 <title id="slowsme">How much does Privoxy slow my browsing down? This
1454 has to add extra time to browsing.</title>
1456 How much of an impact depends on many things, including the CPU of the host
1457 system, how aggressive the configuration is, which specific actions are being triggered,
1458 the size of the page, the bandwidth of the connection, etc.
1461 Overall, it should not slow you down any in real terms, and may actually help
1462 speed things up since ads, banners and other junk are not typically being
1463 retrieved and displayed. The actual processing time required by
1464 <application>Privoxy</application> itself for each page, is relatively small
1465 in the overall scheme of things, and happens very quickly. This is typically
1466 more than offset by time saved not downloading and rendering ad images (if ad
1467 blocking is being used).
1471 <quote>Filtering</quote> content via the <literal><ulink
1472 url="../user-manual/actions-file.html#FILTER">filter</ulink></literal> or
1474 url="../user-manual/actions-file.html#DEANIMATE-GIFS">deanimate-gifs</ulink></literal>
1475 actions may cause a perceived slowdown, since the entire document
1476 needs to be buffered before displaying. And on very large documents, filtering may have
1477 some measurable impact. How much depends on the page size, the actual
1478 definition of the filter(s), etc. See below. Most other actions have little
1479 to no impact on speed.
1482 Also, when filtering is enabled but zlib support isn't available, compression
1483 is often disabled (see <ulink
1484 url="../user-manual/actions-file.html#PREVENT-COMPRESSION">prevent-compression</ulink>).
1485 This can have an impact on speed as well. Again, the page size, etc. will
1486 determine how much of an impact.
1492 <sect2 renderas="sect3" id="loadingtimes"><title>I notice considerable
1493 delays in page requests. What's wrong?</title>
1495 If you use any <literal><ulink
1496 url="../user-manual/actions-file.html#FILTER">filter</ulink></literal> action,
1497 such as filtering banners by size, web-bugs etc, or the <literal><ulink
1498 url="../user-manual/actions-file.html#DEANIMATE-GIFS">deanimate-gifs</ulink></literal>
1499 action, the entire document must be loaded into memory in order for the filtering
1500 mechanism to work, and nothing is sent to the browser during this time.
1503 The loading time typically does not really change much in real numbers, but
1504 the feeling is different, because most browsers are able to start rendering
1505 incomplete content, giving the user a feeling of "it works". This effect is
1506 more noticeable on slower dialup connections. Extremely large documents
1507 may have some impact on the time to load the page where there is filtering
1508 being done. But overall, the difference should be very minimal. If there is a
1509 big impact, then probably some other situation is contributing (like
1510 anti-virus software).
1513 Filtering is automatically disabled for inappropriate MIME types. But note
1514 that if the web server mis-reports the MIME type, then content that should
1515 not be filtered, could be. <application>Privoxy</application> only knows how
1516 to differentiate filterable content because of the MIME type as reported by
1517 the server, or because of some configuration setting that enables/disables
1522 <sect2 renderas="sect3" id="configurl"><title>What are "http://config.privoxy.org/" and
1523 "http://p.p/"?</title>
1525 <ulink url="http://config.privoxy.org/">http://config.privoxy.org/</ulink> is the
1526 address of <application>Privoxy</application>'s built-in user interface, and
1527 <ulink url="http://p.p/">http://p.p/</ulink> is a shortcut for it.
1530 Since <application>Privoxy</application> sits between your web browser and the Internet,
1531 it can simply intercept requests for these addresses and answer them with its built-in
1532 <quote>web server</quote>.
1535 This also makes for a good test for your browser configuration: If entering the
1536 URL <ulink url="http://config.privoxy.org/">http://config.privoxy.org/</ulink>
1537 takes you to a page saying <quote>This is Privoxy ...</quote>, everything is OK.
1538 If you get a page saying <quote>Privoxy is not working</quote> instead, then
1539 your browser didn't use <application>Privoxy</application> for the request,
1540 hence it could not be intercepted, and you have accessed the <emphasis>real</emphasis>
1541 web site at config.privoxy.org.
1547 out of date 09/02/06 HB
1548 <sect2 renderas="sect3" id="blocklist"><title>Do you still maintain the blocklists?</title>
1550 No. The patterns for blocking now reside (among other things) in the <ulink
1551 url="../user-manual/actions-file.html">actions files</ulink>, which are
1552 actively maintained instead. See next question ...
1556 <sect2 renderas="sect3" id="newads"><title>How can I submit new ads, or report
1559 Please see the <link linkend="contact">Contact section</link> for
1560 various ways to interact with the developers.
1565 <sect2 renderas="sect3" id="newads2"><title>If I do submit missed ads, will
1566 they be included in future updates?</title>
1568 Whether such submissions are eventually included in the
1569 <filename>default.action</filename> configuration file depends on how
1570 significant the issue is. We of course want to address any potential
1571 problem with major, high-profile sites such as <citetitle>Google</citetitle>,
1572 <citetitle>Yahoo</citetitle>, etc. Any site with global or regional reach,
1573 has a good chance of being a candidate. But at the other end of the spectrum
1574 are any number of smaller, low-profile sites such as for local clubs or
1575 schools. Since their reach and impact are much less, they are best handled by
1576 inclusion in the user's <filename>user.action</filename>, and thus would be
1577 unlikely to be included.
1583 <sect2 renderas="sect3" id="noonecares"><title>Why doesn't anyone answer my support
1586 Rest assured that it has been read and considered. Why it is not answered,
1587 could be for various reasons, including no one has a good answer for it, no
1588 one has had time to yet investigate it thoroughly, it has been reported
1589 numerous times already, or because not enough information was provided to help
1590 us help you. Your efforts are not wasted, and we do appreciate them.
1596 <sect2 renderas="sect3" id="ip"><title>How can I hide my IP address?</title>
1598 If you run both the browser and &my-app; locally, you cannot hide your IP
1599 address with <application>Privoxy</application> or ultimately any other
1600 software alone. The server needs to know your IP address so that it knows
1601 where to send the responses back.
1604 There are many publicly usable "anonymous" proxies out there, which
1605 provide a further level of indirection between you and the web server.
1608 However, these proxies are called "anonymous" because you don't need
1609 to authenticate, not because they would offer any real anonymity.
1610 Most of them will log your IP address and make it available to the
1611 authorities in case you violate the law of the country they run in. In fact
1612 you can't even rule out that some of them only exist to *collect* information
1613 on (those suspicious) people with a more than average preference for privacy.
1616 Your best bet is to chain <application>Privoxy</application>
1617 with <ulink url="http://tor.eff.org/">Tor</ulink>,
1618 an <ulink url="http://www.eff.org/">EFF</ulink> supported onion routing system.
1619 The configuration details can be found in
1620 <ulink url="#TOR">How do I use <application>Privoxy</application> together
1621 with <application>Tor</application> section</ulink>
1626 <sect2 renderas="sect3">
1627 <title id="anonforsure">Can Privoxy guarantee I am anonymous?</title>
1629 No. Your chances of remaining anonymous are greatly improved, but unless you
1630 <ulink url="#TOR">chain <application>Privoxy</application> with <application>Tor</application></ulink>
1631 or a similar system and know what you're doing when it comes to configuring
1632 the rest of your system, it would be safest to assume that everything you do
1633 on the Web can be traced back to you.
1636 <application>Privoxy</application> can remove various information about you,
1637 and allows <emphasis>you</emphasis> more freedom to decide which sites
1638 you can trust, and what details you want to reveal. But it neither
1639 hides your IP address, nor can it guarantee that the rest of the system
1640 behaves correctly. There are several possibilities how a web sites can find
1641 out who you are, even if you are using a strict <application>Privoxy</application>
1642 configuration and chained it with <application>Tor</application>.
1645 Most of <application>Privoxy's</application> privacy-enhancing features can be easily subverted
1646 by an insecure browser configuration, therefore you should use a browser that can
1647 be configured to only execute code from trusted sites, and be careful which sites you trust.
1648 For example there is no point in having <application>Privoxy</application>
1649 modify the User-Agent header, if websites can get all the information they want
1650 through JavaScript, ActiveX, Flash, Java etc.
1653 A few browsers disclose the user's email address in certain situations, such
1654 as when transferring a file by FTP. <application>Privoxy</application>
1655 does not filter FTP. If you need this feature, or are concerned about the
1656 mail handler of your browser disclosing your email address, you might
1657 consider products such as <application>NSClean</application>.
1660 Browsers available only as binaries could use non-standard headers to give
1661 out any information they can have access to: see the manufacturer's license
1662 agreement. It's impossible to anticipate and prevent every breach of privacy
1663 that might occur. The professionally paranoid prefer browsers available as
1664 source code, because anticipating their behavior is easier. Trust the source,
1670 <sect2 renderas="sect3">
1671 <title id="proxytest">A test site says I am not using a Proxy.</title>
1673 Good! Actually, they are probably testing for some other kinds of proxies.
1674 Hiding yourself completely would require additional steps.
1678 <sect2 renderas="sect3" id="tor"><title>How do I use Privoxy
1679 together with Tor?</title>
1681 Before you configure <application>Privoxy</application> to use
1682 <ulink url="https://www.torproject.org/">Tor</ulink>,
1683 please follow the <citetitle>User Manual</citetitle> chapters
1684 <ulink url="../user-manual/installation.html">2. Installation</ulink> and
1685 <ulink url="../user-manual/startup.html">5. Startup</ulink> to make sure
1686 <application>Privoxy</application> itself is setup correctly.
1689 If it is, refer to <ulink url="https://www.torproject.org/documentation.html">Tor's
1690 extensive documentation</ulink> to learn how to install <application>Tor</application>,
1691 and make sure <application>Tor</application>'s logfile says that
1692 <quote>Tor has successfully opened a circuit</quote> and it
1693 <quote>looks like client functionality is working</quote>.
1696 If either <application>Tor</application> or <application>Privoxy</application>
1697 isn't working, their combination most likely will neither. Testing them on their
1698 own will also help you to direct problem reports to the right audience.
1699 If <application>Privoxy</application> isn't working, don't bother the
1700 <application>Tor</application> developers. If <application>Tor</application>
1701 isn't working, don't send bug reports to the <application>Privoxy</application> Team.
1704 If you verified that <application>Privoxy</application> and <application>Tor</application>
1705 are working, it is time to connect them. As far as <application>Privoxy</application>
1706 is concerned, <application>Tor</application> is just another proxy that can be reached
1707 by socks4 or socks4a. Most likely you are interested in <application>Tor</application>
1708 to increase your anonymity level, therefore you should use socks4a, to make sure DNS requests are
1709 done through <application>Tor</application> and thus invisible to your local network.
1714 Since <application>Privoxy</application> 3.0.5, its
1715 <ulink url="../user-manual/config.html">main configuration file</ulink>
1716 is already prepared for <application>Tor</application>, if you are using a
1717 default <application>Tor</application> configuration and run it on the same
1718 system as &my-app;, you just have to edit the
1719 <ulink url="../user-manual/config.html#FORWARDING">forwarding section</ulink>
1720 and uncomment the line:
1724 # forward-socks4a / 127.0.0.1:9050 .
1728 This is enough to reach the Internet, but additionally you might want to
1729 uncomment the following forward rules, to make sure your local network is still
1730 reachable through Privoxy:
1734 # forward 192.168.*.*/ .
1735 # forward 10.*.*.*/ .
1736 # forward 127.*.*.*/ .
1740 Unencrypted connections to systems in these address ranges will
1741 be as (un)secure as the local network is, but the alternative is
1742 that your browser can't reach the network at all. Then again,
1743 that may actually be desired and if you don't know for sure
1744 that your browser has to be able to reach the local network,
1745 there's no reason to allow it.
1748 If you want your browser to be able to reach servers in your local
1749 network by using their names, you will need additional exceptions
1750 that look like this:
1754 # forward localhost/ .
1758 Save the modified configuration file and open
1759 <ulink url="http://config.privoxy.org/show-status">http://config.privoxy.org/show-status/</ulink>
1760 in your browser, confirm that <application>Privoxy</application> has reloaded its configuration
1761 and that there are no other forward lines, unless you know that you need them. If everything looks good,
1763 <ulink url="https://wiki.torproject.org/wiki/TheOnionRouter/TorFAQ#head-0e1cc2ac330ede8c6ad1ac0d0db0ac163b0e6143">Tor
1764 Faq 4.2</ulink> to learn how to verify that you are really using <application>Tor</application>.
1767 Afterward, please take the time to at least skim through the rest
1768 of <application>Tor's</application> documentation. Make sure you understand
1769 what <application>Tor</application> does, why it is no replacement for
1770 application level security, and why you shouldn't use it for unencrypted logins.
1774 <sect2 renderas="sect3">
1775 <title id="sitebreak">Might some things break because header information or
1776 content is being altered?</title>
1779 Definitely. It is common for sites to use browser type, browser version,
1780 HTTP header content, and various other techniques in order to dynamically
1781 decide what to display and how to display it. What you see, and what I see,
1782 might be very different. There are many, many ways that this can be handled,
1783 so having hard and fast rules, is tricky.
1787 The <quote>User-Agent</quote> is sometimes used in this way to identify
1788 the browser, and adjust content accordingly.
1792 Also, different browsers use different encodings of Russian and Czech
1793 characters, certain web servers convert pages on-the-fly according to the
1794 User Agent header. Giving a <quote>User Agent</quote> with the wrong
1795 operating system or browser manufacturer causes some sites in these languages
1796 to be garbled; Surfers to Eastern European sites should change it to
1797 something closer. And then some page access counters work by looking at the
1798 <quote>Referer</quote> header; they may fail or break if unavailable. The
1799 weather maps of Intellicast have been blocked by their server when no
1800 <quote>Referer</quote> or cookie is provided, is another example. (But you
1801 can forge both headers without giving information away). There are
1802 many other ways things that can go wrong when trying to fool a web server. The
1803 results of which could inadvertently cause pages to load incorrectly,
1804 partially, or even not at all. And there may be no obvious clues as to just
1805 what went wrong, or why. Nowhere will there be a message that says
1806 <quote><emphasis>Turn off <literal>fast-redirects</literal> or else!</emphasis>
1811 Similar thoughts apply to modifying JavaScript, and, to a lesser degree,
1816 If you have problems with a site, you will have to adjust your configuration
1817 accordingly. Cookies are probably the most likely adjustment that may
1818 be required, but by no means the only one.
1824 <sect2 renderas="sect3">
1825 <title id="caching">Can Privoxy act as a <quote>caching</quote> proxy to
1826 speed up web browsing?</title>
1828 No, it does not have this ability at all. You want something like
1829 <ulink url="http://www.squid-cache.org/">Squid</ulink> or
1830 <ulink url="http://www.pps.jussieu.fr/~jch/software/polipo/">Polipo</ulink> for this.
1831 And, yes, before you ask, <application>Privoxy</application> can co-exist
1832 with other kinds of proxies like <application>Squid</application>.
1833 See the <ulink url="../user-manual/config.html#FORWARDING">forwarding
1834 chapter</ulink> in the <ulink url="../user-manual/index.html">user
1835 manual</ulink> for details.
1839 <sect2 renderas="sect3">
1840 <title id="firewall">What about as a firewall? Can Privoxy protect me?</title>
1842 Not in the way you mean, or in the way some firewall vendors claim they can.
1843 <application>Privoxy</application> can help protect your privacy, but can't
1844 protect your system from intrusion attempts. It is, of course, perfectly possible
1845 to use <emphasis>both</emphasis>.
1849 <sect2 renderas="sect3">
1850 <title id="wasted">I have large empty spaces / a checkerboard pattern now where
1851 ads used to be. Why?</title>
1853 It is technically possible to eliminate banners and ads in a way that frees
1854 their allocated page space. This could easily be done by blocking with
1855 <application>Privoxy's</application> filters,
1856 and eliminating the <emphasis>entire</emphasis> image references from the
1860 But, this would consume considerably more CPU resources (IOW, slow things
1861 down), would likely destroy the layout of some web pages which rely on the
1862 banners utilizing a certain amount of page space, and might fail in other
1863 cases, where the screen space is reserved (e.g. by HTML tables for instance).
1864 Also, making ads and banners disappear without any trace complicates
1865 troubleshooting, and would sooner or later be problematic.
1868 The better alternative is to instead let them stay, and block the resulting
1869 requests for the banners themselves as is now the case. This leaves either
1870 empty space, or the familiar checkerboard pattern.
1873 So the developers won't support this in the default configuration, but you
1874 can of course define appropriate filters yourself to achieve this.
1878 <sect2 renderas="sect3">
1879 <title id="ssl">How can Privoxy filter Secure (HTTPS) URLs?</title>
1881 Since secure HTTP connections are encrypted SSL sessions between your browser
1882 and the secure site, and are meant to be reliably <emphasis>secure</emphasis>,
1883 there is little that <application>Privoxy</application> can do but hand the raw
1884 gibberish data though from one end to the other unprocessed.
1887 The only exception to this is blocking by host patterns, as the client needs
1888 to tell <application>Privoxy</application> the name of the remote server,
1889 so that <application>Privoxy</application> can establish the connection.
1890 If that name matches a host-only pattern, the connection will be blocked.
1893 As far as ad blocking is concerned, this is less of a restriction than it may
1894 seem, since ad sources are often identifiable by the host name, and often
1895 the banners to be placed in an encrypted page come unencrypted nonetheless
1896 for efficiency reasons, which exposes them to the full power of
1897 <application>Privoxy</application>'s ad blocking.
1900 <quote>Content cookies</quote> (those that are embedded in the actual HTML or
1901 JS page content, see <literal><ulink
1902 url="../user-manual/actions-file.html#FILTER-CONTENT-COOKIES">filter{content-cookies}</ulink></literal>),
1903 in an SSL transaction will be impossible to block under these conditions.
1904 Fortunately, this does not seem to be a very common scenario since most
1905 cookies come by traditional means.
1910 <sect2 renderas="sect3">
1911 <title id="secure">Privoxy runs as a <quote>server</quote>. How
1912 secure is it? Do I need to take any special precautions?</title>
1914 On Unix-like systems, <application>Privoxy</application> can run as a non-privileged
1915 user, which is how we recommend it be run. Also, by default
1916 <application>Privoxy</application> listens to requests from <quote>localhost</quote>
1920 The server aspect of <application>Privoxy</application> is not itself directly
1921 exposed to the Internet in this configuration. If you want to have
1922 <application>Privoxy</application> serve as a LAN proxy, this will have to
1923 be opened up to allow for LAN requests. In this case, we'd recommend
1924 you specify only the LAN gateway address, e.g. 192.168.1.1, in the main
1925 <application>Privoxy</application> configuration file and check all <ulink
1926 url="../user-manual/config.html#ACCESS-CONTROL">access control and security
1927 options</ulink>. All LAN hosts can then use this as their proxy address
1928 in the browser proxy configuration, but <application>Privoxy</application>
1929 will not listen on any external interfaces. ACLs can be defined in addition,
1930 and using a firewall is always good too. Better safe than sorry.
1935 <sect2 renderas="sect3" id="turnoff">
1936 <title>How can I temporarily disable Privoxy?</title>
1938 The easiest way is to access <application>Privoxy</application> with your
1939 browser by using the remote toggle URL: <ulink
1940 url="http://config.privoxy.org/toggle">http://config.privoxy.org/toggle</ulink>.
1941 See the <ulink url="../user-manual/appendix.html#BOOKMARKLETS">Bookmarklets section</ulink>
1942 of the <citetitle>User Manual</citetitle> for an easy way to access this
1948 <sect2 renderas="sect3" id="reallyoff">
1949 <title>When <quote>disabled</quote> is Privoxy totally
1950 out of the picture?</title>
1952 No, this just means all optional filtering and actions are disabled.
1953 <application>Privoxy</application> is still acting as a proxy, but just not
1954 doing any of the things that <application>Privoxy</application> would
1955 normally be expected to do. It is still a <quote>middle-man</quote> in
1956 the interaction between your browser and web sites. See below to bypass
1961 <sect2 renderas="sect3" id="turnoff2">
1962 <title>How can I tell Privoxy to totally ignore certain sites?</title>
1964 Bypassing a proxy, or proxying based on arbitrary criteria, is purely a browser
1965 configuration issue, not a &my-app; issue. Modern browsers typically do have
1966 settings for not proxying certain sites. Check your browser's help files.
1971 <sect2 renderas="sect3" id="crunch">
1972 <title>My logs show Privoxy <quote>crunches</quote>
1973 ads, but also its own internal CGI pages. What is a <quote>crunch</quote>?</title>
1975 A <quote>crunch</quote> simply means <application>Privoxy</application> intercepted
1976 <emphasis>something</emphasis>, nothing more. Often this is indeed ads or
1977 banners, but <application>Privoxy</application> uses the same mechanism for
1978 trapping requests for its own internal pages. For instance, a request for
1979 <application>Privoxy's</application> configuration page at: <ulink
1980 url="http://config.privoxy.org">http://config.privoxy.org</ulink>, is
1981 intercepted (i.e. it does not go out to the 'net), and the familiar CGI
1982 configuration is returned to the browser, and the log consequently will show
1983 a <quote>crunch</quote>.
1986 Since version 3.0.7, Privoxy will also log the crunch reason.
1987 If you are using an older version you might want to upgrade.
1991 <sect2 renderas="sect3" id="downloads">
1992 <title>Can Privoxy effect files that I download
1993 from a webserver? FTP server?</title>
1995 From the webserver's perspective, there is no difference between
1996 viewing a document (i.e. a page), and downloading a file. The same is true of
1997 <application>Privoxy</application>. If there is a match for a <literal><ulink
1998 url="../user-manual/actions-file.html#BLOCK">block</ulink></literal> pattern,
1999 it will still be blocked, and of course this is obvious.
2002 Filtering is potentially more of a concern since the results are not always
2003 so obvious, and the effects of filtering are there whether the file is simply
2004 viewed, or downloaded. And potentially whether the content is some obnoxious
2005 advertisement, or Mr. Jimmy's latest/greatest source code jewel. Of course,
2006 one of these presumably is <quote>bad</quote> content that we don't want, and
2007 the other is <quote>good</quote> content that we do want.
2008 <application>Privoxy</application> is blind to the differences, and can only
2009 distinguish <quote>good from bad</quote> by the configuration parameters
2010 <emphasis>we</emphasis> give it.
2013 <application>Privoxy</application> knows the differences in files according
2014 to the <quote>Content Type</quote> as reported by the webserver. If this is
2015 reported accurately (e.g. <quote>application/zip</quote> for a zip archive),
2016 then <application>Privoxy</application> knows to ignore these where
2017 appropriate. <application>Privoxy</application> potentially can filter HTML
2018 as well as plain text documents, subject to configuration parameters of
2019 course. Also, documents that are of an unknown type (generally assumed to be
2020 <quote>text/plain</quote>) can be filtered, as will those that might be
2021 incorrectly reported by the webserver. If such a file is a downloaded file
2022 that is intended to be saved to disk, then any content that might have been
2023 altered by filtering, will be saved too, for these (probably rare) cases.
2026 Note that versions later than 3.0.2 do NOT filter document types reported as
2027 <quote>text/plain</quote>. Prior to this, <application>Privoxy</application>
2028 did filter this document type.
2031 In short, filtering is <quote>ON</quote> if a) the content type as reported
2032 by the webserver is appropriate <emphasis>and</emphasis> b) the configuration
2033 allows it (or at least does not disallow it). That's it. There is no magic
2034 cookie anywhere to say this is <quote>good</quote> and this is
2035 <quote>bad</quote>. It's the configuration that lets it all happen or not.
2038 If you download text files, you probably do not want these to be filtered,
2039 particularly if the content is source code, or other critical content. Source
2040 code sometimes might be mistaken for Javascript (i.e. the kind that might
2041 open a pop-up window). It is recommended to turn off filtering for download
2042 sites (particularly if the content may be plain text files and you are using
2043 version 3.0.2 or earlier) in your <filename>user.action</filename> file. And
2044 also, for any site or page where making <emphasis>any</emphasis> changes at
2045 all to the content is to be avoided.
2048 <application>Privoxy</application> does not do FTP at all, only HTTP
2049 and HTTPS (SSL) protocols, so please don't try.
2053 <sect2 renderas="sect3" id="downloads2">
2054 <title>I just downloaded a Perl script, and Privoxy
2055 altered it! Yikes, what is wrong!</title>
2061 <sect2 renderas="sect3" id="hostsfile">
2062 <title>Should I continue to use a <quote>HOSTS</quote> file for ad-blocking?</title>
2064 One time-tested technique to defeat common ads is to trick the local DNS
2065 system by giving a phony IP address for the ad generator in the local
2066 <filename>HOSTS</filename> file, typically using <literal>127.0.0.1</literal>, aka
2067 <literal>localhost</literal>. This effectively blocks the ad.
2070 There is no reason to use this technique in conjunction with
2071 <application>Privoxy</application>. <application>Privoxy</application>
2072 does essentially the same thing, much more elegantly and with much more
2073 flexibility. A large <filename>HOSTS</filename> file, in fact, not only
2074 duplicates effort, but may get in the way and seriously slow down your system.
2075 It is recommended to remove such entries from your <filename>HOSTS</filename> file. If you think
2076 your hosts list is neglected by <application>Privoxy's </application>
2077 configuration, consider adding your list to your <filename>user.action</filename> file:
2084 ads.galore.example.com
2085 etc.example.com</screen>
2089 <sect2 renderas="sect3" id="seealso">
2090 <title>Where can I find more information about Privoxy
2091 and related issues?</title>
2092 <!-- Include seealso.sgml boilerplate: -->
2094 <!-- end boilerplate -->
2099 <ulink url="../user-manual/seealso.html">user-manual</ulink> for
2105 <sect2 renderas="sect3" id="microsuck">
2106 <title>I've noticed that Privoxy changes <quote>Microsoft</quote> to
2107 <quote>MicroSuck</quote>! Why are you manipulating my browsing?</title>
2110 We're not. The text substitutions that you are seeing are disabled
2111 in the default configuration as shipped. You have either manually
2112 activated the <quote><literal>fun</literal></quote> filter which
2113 is clearly labeled <quote>Text replacements for subversive browsing
2114 fun!</quote> or you are using an older Privoxy version and have implicitly
2115 activated it by choosing the <quote>Adventuresome</quote> profile in the
2116 web-based editor. Please upgrade!
2120 <sect2 renderas="sect3" id="valid">
2121 <title>Does Privoxy produce <quote>valid</quote> HTML (or XHTML)?</title>
2124 Privoxy generates HTML in both its own <quote>templates</quote>, and possibly
2125 whenever there are text substitutions via a &my-app; filter. While this
2126 should always conform to the HTML 4.01 specifications, it has not been
2127 validated against this or any other standard.
2135 <!-- ~~~~~ New section ~~~~~ -->
2137 <sect1 id="trouble">
2138 <title>Troubleshooting</title>
2140 <sect2 renderas="sect3">
2141 <title id="refused">I cannot connect to any websites. Or, I am getting
2142 <quote>connection refused</quote> message with every web page. Why?</title>
2144 There are several possibilities:
2149 <application>Privoxy</application> is not running. Solution: verify
2150 that &my-app; is installed correctly, has not crashed, and is indeed running.
2151 Turn on <application>Privoxy's</application> logging and look at the logs to see what they say.
2153 <listitem><para>Or your browser is configured for a different port than what
2154 <application>Privoxy</application> is using. Solution: verify that &my-app;
2155 and your browser are set to the same port (<literal>listen-address</literal>).
2157 <listitem><para>Or if using a forwarding rule, you have a configuration problem or a
2158 problem with a host in the forwarding chain. Solution: temporarily alter your
2159 configuration and take the forwarders out of the equation.
2162 Or you have a firewall that is interfering and blocking you. Solution:
2163 try disabling or removing the firewall as a simple test.
2170 <!-- ~~~~~ New section ~~~~~ -->
2171 <sect2 renderas="sect3" id="error503">
2172 <title>Why am I getting a 503 Error (WSAECONNREFUSED) on every page?</title>
2174 More than likely this is a problem with your TCP/IP networking. ZoneAlarm has
2175 been reported to cause this symptom -- even if not running! The solution is
2176 to either fight the ZA configuration, or uninstall ZoneAlarm, and then find
2177 something better behaved in its place. Other personal firewall type products
2178 may cause similar type problems if not configured correctly.
2182 <sect2 renderas="sect3">
2183 <title id="flushit">I just added a new rule, but the steenkin ad is
2184 still getting through. How?</title>
2186 If the ad had been displayed before you added its URL, it will probably be
2187 held in the browser's cache for some time, so it will be displayed without
2188 the need for any request to the server, and <application>Privoxy</application>
2189 will not be involved. Flush the browser's caches, and then try again.
2193 If this doesn't help, you probably have an error in the rule you
2194 applied. Try pasting the full URL of the offending ad into <ulink
2195 url="http://config.privoxy.org/show-url-info">http://config.privoxy.org/show-url-info</ulink>
2196 and see if it really matches your new rule. Blocking ads is like blocking
2197 spam: a lot of tinkering is required to stay ahead of the game. And
2198 remember you need to block the URL of the ad in question, which may be
2199 entirely different from the site URL itself. Most ads are hosted on different
2200 servers than the main site itself. If you right-click on the ad, you should
2201 be able to get all the relevant information you need. Alternately, you can
2202 find the correct URL by looking at <application>Privoxy's</application> logs.
2205 Below is a slightly modified real-life log snippet that originates with one
2206 requested URL: <literal>www.example.com</literal> (name of site was changed
2207 for this example, the number of requests is real). You can see in this the
2208 complexity of what goes into making up this one <quote>page</quote>. There
2209 are eight different domains involved here, with thirty two separate URLs
2210 requested in all, making up all manner of images, Shockwave Flash,
2211 JavaScript, CSS stylesheets, scripts, and other related content. Some of this
2212 content is obviously <quote>good</quote> or <quote>bad</quote>, but not all.
2213 Many of the more questionable looking requests, are going to outside domains
2214 that seem to be identifying themselves with suspicious looking names, making
2215 our job a little easier. &my-app; has <quote>crunched</quote> (meaning caught
2216 and BLOCKED) quite a few items in this example, but perhaps missed a few as well.
2221 Request: www.example.com/
2222 Request: www.example.com/favicon.ico
2223 Request: img.example.com/main.css
2224 Request: img.example.com/sr.js
2225 Request: example.betamarker.com/example.html
2226 Request: www.lik-sang.com/Banners/bestsellers/skyscraper.php?likref=BSellers
2227 Request: img.example.com/pb.png
2228 Request: www.google-analytics.com/urchin.js crunch!
2229 Request: www.advertising-department.com/ats/switch.ps.php?26856 crunch!
2230 Request: img.example.com/p.gif
2231 Request: www.popuptraffic.com/assign.php?l=example&mode=behind crunch!
2232 Request: www.popuptraffic.com/scripts/popup.php?hid=5c3cf&tmpl=PBa.tmpl crunch!
2233 Request: www.popuptraffic.com/assign.php?l=example crunch!
2234 Request: www.lik-sang.com/Banners/best_sellers/best_sellers.css
2235 Request: www.adtrak.net/adx.js crunch!
2236 Request: img.example.com/hbg.gif
2237 Request: img.example.com/example.jpg
2238 Request: img.example.com/mt.png
2239 Request: img.example.com/mm.png
2240 Request: img.example.com/mb.png
2241 Request: www.popuptraffic.com/scripts/popup.php?hid=a71b91fa5&tmpl=Ua.tmp crunch!
2242 Request: www.example.com/tracker.js
2243 Request: www.lik-sang.com/Banners/best_sellers/lsi_head.gif
2244 Request: www.adtrak.net/adjs.php?n=020548130&what=zone:61 crunch!
2245 Request: www.adtrak.net/adjs.php?n=463594413&what=zone:58&source=Ua crunch!
2246 Request: www.lik-sang.com/Banners/best_sellers/bottomani.swf
2247 Request: mmm.elitemediagroup.net/install.php?allowpop=no&popupmincook=0&allowsp2=1 crunch!
2248 Request: www.example.com/tracker.js?screen=1400x1050&win=962x693
2249 Request: www.adtrak.net/adlog.php?bannerid=1309&clientid=439&zoneid=61 crunch!
2250 Request: 66.70.21.80/scripts/click.php?hid=5c3cf599a9efd0320d26&si
2251 Request: 66.70.21.80/img/pixel.gif
2252 Request: www.adtrak.net/adlog.php?bannerid=1309&clientid=439&zoneid=58&source=Ua&block=86400 crunch!
2253 Request: 66.70.21.80/scripts/click.php?hid=a71b9f6504b0c5681fa5&si=Ua
2258 Despite 12 out of 32 requests being blocked, the page looked, and seemed to
2259 behave perfectly <quote>normal</quote> (minus some ads, of course).
2264 <sect2 id="badsite" renderas="sect3">
2265 <title >One of my favorite sites does not work with Privoxy.
2266 What can I do?</title>
2269 First verify that it is indeed a <application>Privoxy</application> problem,
2270 by toggling off <application>Privoxy</application> through <ulink
2271 url="http://config.privoxy.org/toggle">http://config.privoxy.org/toggle</ulink>,
2272 and then shift-reloading the problem page (i.e. holding down the shift key
2273 while clicking reload. Alternatively, flush your browser's disk and memory
2278 If the problem went away, we know we have a configuration related problem.
2280 url="http://config.privoxy.org/show-url-info">http://config.privoxy.org/show-url-info</ulink>
2281 and paste the full URL of the page in question into the prompt. See which
2282 actions are being applied to the URL, and which matches in which actions
2283 files are responsible for that. It might be helpful also to look at your logs
2284 for this site too, to see what else might be happening. Many sites are
2285 complex and require a number of related pages to help present their content.
2286 Look at what else might be used by the page in question, and what of that
2287 might be <emphasis>required</emphasis>.
2288 Now, armed with this information, go to
2290 url="http://config.privoxy.org/show-status">http://config.privoxy.org/show-status</ulink>
2291 and select the appropriate actions files for editing. </para>
2293 You can now either look for a section which disables the actions that
2294 you suspect to cause the problem and add a pattern for your site there,
2295 or make up a completely new section for your site. In any case, the recommended
2296 way is to disable only the prime suspect, reload the problem page, and only
2297 if the problem persists, disable more and more actions until you have
2298 identified the culprit. You may or may not want to turn the other actions
2299 on again. Remember to flush your browser's caches in between any such changes!
2302 Alternately, if you are comfortable with a text editor, you can accomplish
2303 the same thing by editing the appropriate actions file. Probably the easiest
2304 way to deal with such problems when editing by hand is to add your
2305 site to a <literal>{ fragile }</literal> section in <filename>user.action</filename>,
2306 which is an alias that turns off most <quote>dangerous</quote>
2307 actions, but is also likely to turn off more actions then needed, and thus lower
2308 your privacy and protection more than necessary,
2311 Troubleshooting actions is discussed in more detail in the <ulink
2312 url="../user-manual/appendix.html#ACTIONSANAT">User Manual appendix,
2313 Troubleshooting: the Anatomy of an Action</ulink>.
2314 There is also an <ulink
2315 url="../user-manual/actions-file.html#ACT-EXAMPLES">actions tutorial</ulink>
2316 with general configuration information and examples.
2319 As a last resort, you can always see if your browser has a setting that will
2320 bypass the proxy setting for selective sites. Modern browsers can do this.
2326 <!-- ~~~~~ New section ~~~~~ -->
2327 <sect2 id="dun" renderas="sect3">
2328 <title>After installing Privoxy, I have to log in
2329 every time I start IE. What gives?</title>
2332 This is a quirk that effects the installation of
2333 <application>Privoxy</application>, in conjunction with Internet Explorer and
2334 Internet Connection Sharing on Windows 2000 and Windows XP. The symptoms may
2335 appear to be corrupted or invalid DUN settings, or passwords.
2339 When setting up an NT based Windows system with
2340 <application>Privoxy</application> you may find that things do not seem to be
2341 doing what you expect. When you set your system up you will probably have set
2342 up Internet Connection Sharing (ICS) with Dial up Networking (DUN) when
2343 logged in with administrator privileges. You will probably have made this DUN
2344 connection available to other accounts that you may have set-up on your
2345 system. E.g. Mum or Dad sets up the system and makes accounts suitably
2346 configured for the kids.
2350 When setting up <application>Privoxy</application> in this environment you
2351 will have to alter the proxy set-up of Internet Explorer (IE) for the
2352 specific DUN connection on which you wish to use
2353 <application>Privoxy</application>. When you do this the ICS DUN set-up
2354 becomes user specific. In this instance you will see no difference if you
2355 change the DUN connection under the account used to set-up the connection.
2356 However when you do this from another user you will notice that the DUN
2357 connection changes to make available to "Me only". You will also find that
2358 you have to store the password under each different user!
2362 The reason for this is that each user's set-up for IE is user specific. Each
2363 set-up DUN connection and each LAN connection in IE store the settings for
2364 each user individually. As such this enforces individual configurations
2365 rather than common ones. Hence the first time you use a DUN connection after
2366 re-booting your system it may not perform as you expect, and prompt you for
2367 the password. Just set and save the password again and all should be OK.
2371 [Thanks to Ray Griffith for this submission.]
2376 <!-- ~~~~~ New section ~~~~~ -->
2377 <sect2 id="ftp" renderas="sect3">
2378 <title>I cannot connect to any FTP sites. Privoxy
2379 is blocking me.</title>
2381 <application>Privoxy</application> cannot act as a proxy for FTP traffic,
2382 so do not configure your browser to use <application>Privoxy</application>
2383 as an FTP proxy. The same is true for <emphasis>any protocol other than HTTP
2384 or HTTPS (SSL)</emphasis>.
2387 Most browsers understand FTP as well as HTTP. If you connect to a site, with
2388 a URL like <literal>ftp://ftp.example.com</literal>, your browser is making
2389 an FTP connection, and not a HTTP connection. So while your browser may
2390 speak FTP, <application>Privoxy</application> does not, and cannot proxy
2394 To complicate matters, some systems may have a generic <quote>proxy</quote>
2395 setting, which will enable various protocols, including
2396 <emphasis>both</emphasis> HTTP and FTP proxying! So it is possible to
2397 accidentally enable FTP proxying in these cases. And of course, if this
2398 happens, <application>Privoxy</application> will indeed cause problems since
2399 it does not know FTP. <![%p-newstuff;[Newer version will give a sane error
2400 message if a FTP connection is attempted.]]> Just disable the FTP setting
2401 and all will be well again.
2404 Will <application>Privoxy</application> ever proxy FTP traffic? Unlikely.
2405 There just is not much reason, and the work to make this happen is more than
2410 <!-- ~~~~~ New section ~~~~~ -->
2411 <sect2 id="osxie" renderas="sect3">
2412 <title>In Mac OSX, I can't configure Microsoft Internet Explorer to use
2413 Privoxy as the HTTP proxy.</title>
2415 Microsoft Internet Explorer (in versions like 5.1) respects system-wide
2416 network settings. In order to change the HTTP proxy, open System
2417 Preferences, and click on the Network icon. In the settings pane that
2418 comes up, click on the Proxies tab. Ensure the "Web Proxy (HTTP)" checkbox
2419 is checked and enter <literal>127.0.0.1</literal> in the entry field.
2420 Enter <literal>8118</literal> in the Port field. The next time you start
2421 IE, it should reflect these values.
2425 <!-- ~~~~~ New section ~~~~~ -->
2426 <sect2 renderas="sect3" id="osxuninstall">
2427 <title>In Mac OSX, I dragged the Privoxy folder to the trash in order to
2428 uninstall it. Now the finder tells me I don't have sufficient privileges to
2429 empty the trash.</title>
2431 Just dragging the <application>Privoxy</application> folder to the trash is
2432 not enough to delete it. <application>Privoxy</application> supplies an
2433 <application>uninstall.command</application> file that takes care of
2434 these details. Open the trash, drag the <application>uninstall.command</application>
2435 file out of the trash and double-click on it. You will be prompted for
2436 confirmation and the administration password.
2439 The trash may still appear full after this command; emptying the trash
2440 from the desktop should make it appear empty again.
2445 <!-- ~~~~~ New section ~~~~~ -->
2446 <sect2 renderas="sect3" id="osximages">
2447 <title>In Mac OSX Panther (10.3), images often fail to load and/or I
2448 experience random delays in page loading. I'm using
2449 <literal>localhost</literal> as my browser's proxy setting.</title>
2451 We believe this is due to an IPv6-related bug in OSX, but don't fully
2452 understand the issue yet. In any case, changing the proxy setting to
2453 <literal>127.0.0.1</literal> instead of <literal>localhost</literal>
2454 works around the problem.
2458 <!-- ~~~~~ New section ~~~~~ -->
2459 <sect2 renderas="sect3" id="blankpage">
2460 <title>I get a completely blank page at one site. <quote>View Source</quote>
2461 shows only: <markup><![CDATA[<html><body></body></html>]]></markup>. Without
2462 Privoxy the page loads fine.</title>
2464 Chances are that the site suffers from a bug in
2465 <ulink url="http://www.php.net/"><application>PHP</application></ulink>,
2466 which results in empty pages being sent if the client explicitly requests
2467 an uncompressed page, like <application>Privoxy</application> does.
2468 This bug has been fixed in PHP 4.2.3.
2471 To find out if this is in fact the source of the problem, try adding
2472 the site to a <literal>-prevent-compression</literal> section in
2473 <filename>user.action</filename>:
2476 # Make exceptions for ill-behaved sites:
2478 {-prevent-compression}
2479 .example.com</screen>
2481 If that works, you may also want to report the problem to the
2482 site's webmasters, telling them to use zlib.output_compression
2483 instead of ob_gzhandler in their PHP applications (workaround)
2484 or upgrade to PHP 4.2.3 or later (fix).
2488 <sect2 renderas="sect3" id="nohostname">
2489 <title>My logs show many <quote>Unable to get my own hostname</quote> lines.
2492 <application>Privoxy</application> tries to get the hostname of the system
2493 its running on from the IP address of the system interface it is bound to
2494 (from the <filename>config</filename> file
2495 <emphasis>listen-address</emphasis> setting). If the system cannot supply
2496 this information, <application>Privoxy</application> logs this condition.
2499 Typically, this would be considered a minor system configuration error. It is
2500 not a fatal error to <application>Privoxy</application> however, but may
2501 result in a much slower response from <application>Privoxy</application> on
2502 some platforms due to DNS timeouts.
2505 This can be caused by a problem with the local <filename>HOSTS</filename>
2506 file. If this file has been changed from the original, try reverting it to
2507 see if that helps. Make sure whatever name(s) are used for the local system,
2508 that they resolve both ways.
2512 <sect2 renderas="sect3" id="inuse">
2513 <title>When I try to launch Privoxy, I get an
2514 error message <quote>port 8118 is already in use</quote> (or similar wording).
2517 Port 8118 is <application>Privoxy's</application> default TCP
2518 <quote>listening</quote> port. Typically this message would mean that there
2519 is already one instance of <application>Privoxy</application> running, and
2520 your system is actually trying to start a second
2521 <application>Privoxy</application> on the same port, which will not work.
2522 (You can have multiple instances but they must be assigned different ports.)
2523 How and why this might happen varies from platform to platform, but you need
2524 to check your installation and start-up procedures.
2528 <sect2 renderas="sect3" id="demoronizer">
2530 Pages with UTF-8 fonts are garbled.
2533 This is caused by the <quote>demoronizer</quote> filter. You should either
2534 upgrade <application>Privoxy</application>, or at least upgrade to the most
2535 recent <filename>default.action</filename> file available from <ulink
2536 url="http://sourceforge.net/project/showfiles.php?group_id=11118">SourceForge</ulink>.
2537 Or you can simply disable the demoronizer filter.
2541 <sect2 renderas="sect3" id="demoronizer2">
2543 Why are binary files (such as images) corrupted when Privoxy
2547 This may also be caused by the <quote>demoronizer</quote> filter,
2548 in conjunction with a web server that is misreporting the content type. Binary
2549 files are exempted from <application>Privoxy's</application> filtering
2550 (unless the web server by mistake says the file is something else). Either
2551 upgrade <application>Privoxy</application>, or go to the most recent
2552 <filename>default.action</filename> file available from <ulink
2553 url="http://sourceforge.net/project/showfiles.php?group_id=11118">SourceForge</ulink>.
2557 <sect2 renderas="sect3" id="demoronizer3">
2559 What is the <quote>demoronizer</quote> and why is it there?
2562 The original demoronizer was a Perl script that cleaned up HTML pages which
2563 were created with certain Microsoft products. MS has used proprietary extensions
2564 to standardized font encodings (ISO 8859-1), which has caused problems for pages
2565 that are viewed with non-Microsoft products (and are expecting to see a
2566 standard set of fonts). The demoronizer corrected these errors so the pages
2567 displayed correctly. <application>Privoxy</application> borrowed from this
2568 script, introducing a filter based on the original demoronizer, which in turn could
2569 correct these errors on the fly.
2572 But this is only needed in some situations, and will cause serious problems in some
2576 If you are using Microsoft products, you do not need it. If you need to view
2577 pages with UTF-8 characters (such as Cyrillic or Chinese), then it will
2578 cause corruption of the fonts, and thus <emphasis>should not be on</emphasis>.
2581 On the other hand, if you use non-Microsoft products, and you occasionally
2582 notice wierd characters on pages, you might want to try it.
2586 <sect2 renderas="sect3" id="windowopen">
2588 Why do I keep seeing <quote>PrivoxyWindowOpen()</quote> in raw source code?
2591 <application>Privoxy</application> is attempting to disable malicious
2592 <ulink url="http://en.wikipedia.org/wiki/Javascript">Javascript</ulink>
2593 in this case, with the <literal>unsolicited-popups</literal>
2594 filter. <application>Privoxy</application> cannot tell very well
2595 <quote>good</quote> code snippets from <quote>bad</quote> code snippets.
2598 If you see this in HTML source, and the page displays without problems, then
2599 this is good, and likely some pop-up window was disabled. If you see this
2600 where it is causing a problem, such as a downloaded program source code file,
2601 then you should set an exception for this site or page such that the
2602 integrity of the page stays in tact by disabling all filtering.
2606 <sect2 renderas="sect3" id="dnserrors">
2608 I am getting too many DNS errors like <quote>404 No Such Domain</quote>. Why
2609 can't Privoxy do this better?
2612 There are potentially several factors here. First of all, the DNS resolution
2613 is done by the underlying operating system -- not
2614 <application>Privoxy</application> itself. <application>Privoxy</application>
2615 merely initiates the process and hands it off, and then later reports
2616 whatever the outcome was. And tries to give a coherent message if there seems
2617 to be a problem. In some cases, this might otherwise be mitigated by the
2618 browser itself which might try some work-arounds and alternate approaches (e.g
2619 adding <quote>www.</quote> to the URL). In other cases, if
2620 <application>Privoxy</application> is being chained with another proxy, this
2621 could complicate the issue, and cause undue
2622 delays and timeouts. In the case of a <quote>socks4a</quote> proxy, the socks
2623 server handles all the DNS. <application>Privoxy</application> would just be
2624 the <quote>messenger</quote> which is reporting whatever problem occurred
2625 downstream, and not the root cause of the error.
2629 In any case, newer versions include various improvements to help
2630 <application>Privoxy</application> better handle these cases.
2634 <sect2 renderas="sect3" id="allcpu">
2636 At one site Privoxy just hangs, and starts taking
2637 all CPU. Why is this?
2640 This is probably a manifestation of the <quote>100% cpu</quote> problem that
2641 occurs on pages containing many (thousands upon thousands) of blank lines. The blank lines
2642 are in the raw HTML source of the page, and the browser just ignores them. But the
2643 pattern matching in <application>Privoxy's</application> page filtering
2644 mechanism is trying to match against absurdly long strings and this becomes
2645 very CPU-intensive, taking a long, long time to complete. Until a better
2646 solution comes along, disable filtering on these pages, particularly the
2647 <literal>js-annoyances</literal> and <literal>unsolicited-popups</literal>
2652 <sect2 renderas="sect3" id="slowcrawl">
2653 <title>I just installed Privoxy, and all my
2654 browsing has slowed to a crawl. What gives? </title>
2656 This should not happen, and for the overwhelming number of users world-wide,
2657 it does not happen. I would suspect some inadvertent interaction of software
2658 components such as anti-virus software, spyware protectors, personal
2659 firewalls or similar components. Try disabling (or uninstalling) these one
2660 at a time and see if that helps.
2664 <sect2 renderas="sect3" id="preventcomp">
2665 <title>Why do my filters work on some sites but not on others? </title>
2667 It's probably due to compression. It is a common practice for web servers to
2668 send their content <quote>compressed</quote> in order to speed things up, and
2669 then let the browser <quote>uncompress</quote> them. When compiled with zlib support
2670 &my-app; can decompress content before filtering, otherwise you may want to enable
2672 url="../user-manual/actions-file.html#PREVENT-COMPRESSION">prevent-compression</ulink>.
2679 <!-- ~~~~~ New section ~~~~~ -->
2680 <sect1 id="contact"><title>Contacting the developers, Bug Reporting and Feature Requests</title>
2681 <!-- Include contacting.sgml -->
2683 <!-- end contacting -->
2686 <!-- ~~~~~ New section ~~~~~ -->
2687 <sect1 id="copyright"><title>Privoxy Copyright, License and History</title>
2689 <!-- Include copyright.sgml -->
2695 Portions of this document are <quote>borrowed</quote> from the original
2696 <application>Junkbuster</application> (tm) FAQ, and modified as
2697 appropriate for <application>Privoxy</application>.
2700 <!-- ~~~~~ New section ~~~~~ -->
2701 <sect2><title>License</title>
2702 <!-- Include copyright.sgml: -->
2704 <!-- end copyright -->
2706 <!-- ~ End section ~ -->
2708 <!-- ~~~~~ New section ~~~~~ -->
2709 <sect2><title>History</title>
2710 <!-- Include history.sgml -->
2716 <!-- ~ End section ~ -->
2719 <!-- ~~~~~ New section ~~~~~ -->
2721 <sect1 id="seealso"><title>See also</title>
2723 <!-- Include seealso.sgml -->
2734 Tue 09/11/01 06:38:14 PM EST: Test SGML doc by Hal Burgiss.
2736 This program is free software; you can redistribute it
2737 and/or modify it under the terms of the GNU General
2738 Public License as published by the Free Software
2739 Foundation; either version 2 of the License, or (at
2740 your option) any later version.
2742 This program is distributed in the hope that it will
2743 be useful, but WITHOUT ANY WARRANTY; without even the
2744 implied warranty of MERCHANTABILITY or FITNESS FOR A
2745 PARTICULAR PURPOSE. See the GNU General Public
2746 License for more details.
2748 The GNU General Public License should be included with
2749 this file. If not, you can view it at
2750 http://www.gnu.org/copyleft/gpl.html
2751 or write to the Free Software Foundation, Inc.,
2752 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
2755 Revision 2.28 2007/10/27 15:14:16 fabiankeil
2756 Change Tor links to use the new domain torproject.org.
2758 Revision 2.27 2007/10/22 19:47:05 fabiankeil
2759 - Bump version and copyright.
2760 - Adjust Tor section to make it clear that forward exceptions
2761 aren't required and may not even be desired.
2762 - A bunch of other minor rewordings.
2763 - Fix markup problems Roland noticed (hopefully without adding new ones).
2765 Revision 2.26 2007/08/05 15:37:55 fabiankeil
2766 - Don't claim that thousands of people read our code.
2767 - Specify the GPL version and link to GPLv2 instead of v3.
2768 - Note that configuration syntax may change between releases.
2769 - Mention zlib support.
2770 - Answer the "transparent proxy" question properly.
2771 - Add "intercepting proxy" entry.
2773 - Rephrase some other sentences for various reasons.
2775 Revision 2.25 2007/07/18 11:00:34 hal9
2776 Add misc note about valid mark-up in Privoxy.
2778 Revision 2.24 2006/11/14 01:57:46 hal9
2779 Dump all docs prior to 3.0.6 release. Various minor changes to faq and user
2782 Revision 2.23 2006/10/21 22:19:52 hal9
2783 Two new FAQs, a rewrite or two, and some touch ups.
2785 Revision 2.22 2006/10/14 20:33:10 hal9
2786 Three new FAQ's re: templates and blocking, and various minor touch-ups/improvements.
2788 Revision 2.21 2006/10/03 14:40:51 fabiankeil
2789 Added links from the Tor faq to the
2790 configuration chapter in the User Manual.
2792 Revision 2.20 2006/09/26 10:12:37 fabiankeil
2795 Revision 2.19 2006/09/22 10:54:32 hal9
2796 Change references to 3.0.4 to 3.0.5 and minor adjustments.
2798 Revision 2.18 2006/09/22 01:27:55 hal9
2799 Final commit of probably various minor changes here and there. Unless
2800 something changes this should be ready for pending release.
2802 Revision 2.17 2006/09/17 14:56:32 hal9
2803 This includes yet several more new FAQs, some improved wording, enhanced
2804 mark-up, various hyper links to wikipedia to explain key terminology to the
2805 uninitiated, etc. This is ready for release IMO pending final tagging of cvs
2806 and Privoxy version stamping.
2808 Revision 2.16 2006/09/10 15:30:46 hal9
2811 Revision 2.15 2006/09/08 23:05:07 hal9
2812 Fix broken links. Add faq on hosts files. Move most of new windows service
2813 feature to user manual and reference in faq. Various other small changes.
2815 Revision 2.14 2006/09/05 13:25:12 david__schmidt
2816 Add Windows service invocation stuff (duplicated) in FAQ and in user manual under Windows startup. One probably ought to reference the other.
2818 Revision 2.13 2006/09/04 19:20:33 fabiankeil
2819 Adjusted anonymity related sections to match reality.
2820 Added a section about using Privoxy with Tor.
2822 Revision 2.12 2006/09/03 14:15:30 hal9
2823 Various updates, including 7 or 8 new FAQs, and updates/changes to various
2824 other ones to better reflect improvements, additions and changes for the
2825 upcoming release. This is close to final form for 3.0.4 IMHO.
2827 Revision 2.11 2006/07/18 14:48:50 david__schmidt
2828 Reorganizing the repository: swapping out what was HEAD (the old 3.1 branch)
2829 with what was really the latest development (the v_3_0_branch branch)
2831 Revision 1.61.2.41 2004/04/05 13:44:05 oes
2832 Fixed allow-all-cookies alias name; closes SR #929746
2834 Revision 1.61.2.40 2004/01/30 17:00:33 oes
2835 Added OSX Panther problem
2837 Revision 1.61.2.39 2004/01/29 22:53:08 hal9
2838 Minor changes for exempting docs of text/plain. Change copyright date.
2840 Revision 1.61.2.38 2003/12/10 03:39:45 hal9
2841 Added FAQs for: demoronizer, related problems and why its included. Also,
2842 port 8118 already in use questions, and PrivoxyWindowOpen() questions. All in
2843 troubleshooting section.
2845 Revision 1.61.2.37 2003/10/17 11:01:50 oes
2846 Added Q&A for "not being used" page problem
2848 Revision 1.61.2.36 2003/06/26 23:49:20 hal9
2849 More on the filter/source code problem.
2851 Revision 1.61.2.35 2003/06/26 13:38:08 hal9
2852 Add FAQ on whether configuring Privoxy is necessary or not.
2854 Revision 1.61.2.34 2003/06/26 03:00:03 hal9
2855 Sorry, found another copyright date.
2857 Revision 1.61.2.33 2003/06/26 02:57:05 hal9
2858 Fix typo (finally!) and very minor modifications.
2860 Revision 1.61.2.32 2003/06/26 02:52:04 hal9
2863 Revision 1.61.2.31 2003/06/25 01:27:51 hal9
2864 Fix copyright, and a few nits.
2866 Revision 1.61.2.30 2003/06/25 01:13:52 hal9
2869 - FAQ on "Unable to get my own hostname"
2870 - Another one on filtering effects on text files.
2872 Revision 1.61.2.29 2003/06/15 21:32:58 hal9
2873 Add to the 4.17 (filtering effects on downloaded files).
2875 Revision 1.61.2.28 2003/03/18 19:37:21 oes
2876 s/Advanced|Radical/Adventuresome/g to avoid complaints re fun filter
2878 Revision 1.61.2.27 2002/12/01 06:31:58 hal9
2879 Add faq on win32 error 503 due to ZoneAlarm.
2881 Revision 1.61.2.26 2002/11/17 06:41:06 hal9
2882 Move default profiles table from FAQ to U-M, and other minor related changes.
2885 Revision 1.61.2.25 2002/10/29 03:21:50 hal9
2886 Add 3 Q/A's relating to HTML in email. Other minor touchups.
2888 Revision 1.61.2.24 2002/10/15 12:50:22 oes
2889 s/Advanced/Radical/ (stupid me)
2891 Revision 1.61.2.23 2002/10/15 12:38:56 oes
2892 Added Microsuck faq; more detail for PHP problem
2894 Revision 1.61.2.22 2002/10/12 01:13:13 hal9
2895 Updates for demoronizer, more commentary on Radical profile, and update on
2896 the srvany.exe/icon fix.
2898 Revision 1.61.2.21 2002/10/10 04:09:35 hal9
2899 s/Advanced/Radical/ and added very brief note.
2901 Revision 1.61.2.20 2002/09/26 01:22:45 hal9
2902 Small additions for LAN setup, content-cookies/SSL, and FTP non-support.
2904 Revision 1.61.2.19 2002/08/25 23:31:56 hal9
2905 Fix one grammatical error. Add brief FAQ relating to tranparent proxies (ie
2906 port 80 setting). Add FAQ on effects of Privoxy on downloaded files
2907 (especially filtering).
2909 Revision 1.61.2.18 2002/08/14 16:39:37 hal9
2910 Fix wrong tag on FAQ addition.
2912 Revision 1.61.2.17 2002/08/14 00:01:18 hal9
2915 Revision 1.61.2.16 2002/08/13 00:10:38 hal9
2916 Add faq to troubleshooting re: blank page syndrome, ie {-prevent-compression}.
2918 Revision 1.61.2.15 2002/08/10 11:34:22 oes
2919 Add disclaimer about probably being out-of-date
2921 Revision 1.61.2.14 2002/08/07 02:53:43 hal9
2922 Fix some minor markup errors, and move one OSX Q/A to troubleshooting section.
2924 Revision 1.61.2.13 2002/08/06 11:55:32 oes
2925 Added missing close tag
2927 Revision 1.61.2.12 2002/08/06 11:43:46 david__schmidt
2928 Updated OSX uninstall FAQ... we have an uninstall script now.
2930 Revision 1.61.2.11 2002/08/06 08:54:03 oes
2931 Style police: Fixed formatting details
2933 Revision 1.61.2.10 2002/08/02 14:00:25 david__schmidt
2934 Made the OSX removal commands far less dangerous
2936 Revision 1.61.2.9 2002/08/02 13:14:45 oes
2937 Added warning about sudo rm -r for Mac OSX deinstallation; moved this item to install section
2939 Revision 1.61.2.8 2002/08/02 02:01:42 david__schmidt
2940 Add FAQ item for MSIE on OSX HTTP proxy confusion
2942 Revision 1.61.2.7 2002/08/02 01:46:01 david__schmidt
2943 Added FAQ item for Mac OSX uninstall woes
2945 Revision 1.61.2.6 2002/07/30 20:04:56 hal9
2946 Fix typo: 'schould'.
2948 Revision 1.61.2.5 2002/07/26 15:22:58 oes
2949 - Updated to reflect changes in standard.action
2950 - Added info on where to get updated actions files
2952 Revision 1.61.2.4 2002/07/25 21:42:29 hal9
2953 Add brief notes on not proxying non-HTTP protocols.
2955 Revision 1.61.2.3 2002/06/09 16:36:33 hal9
2956 Clarifications on filtering and MIME. Hardcode 'latest release' in index.html.
2958 Revision 1.61.2.2 2002/06/06 02:51:34 hal9
2959 Fix typo in URL http:/config.privoxy.org
2961 Revision 1.61.2.1 2002/06/05 23:10:43 hal9
2962 Add new FAQ re: DUN/IE. Change release date from May to June :)
2964 Revision 1.61 2002/05/25 12:37:25 hal9
2965 Various minor changes and edits.
2967 Revision 1.60 2002/05/22 17:17:48 oes
2968 Proofread & added more links into u-m
2970 Revision 1.59 2002/05/15 04:03:30 hal9
2971 Fix ulink -> link markup.
2973 Revision 1.58 2002/05/10 01:48:20 hal9
2974 This is mostly proposed copyright/licensing additions and changes. Docs
2975 are still GPL, but licensing and copyright are more visible. Also, copyright
2976 changed in doc header comments (eliminate references to JB except FAQ).
2978 Revision 1.57 2002/05/05 20:26:02 hal9
2979 Sorting out license vs copyright in these docs.
2981 Revision 1.56 2002/05/04 08:44:44 swa
2984 Revision 1.55 2002/05/04 00:41:56 hal9
2985 -Remove TOC/first page kludge in favor of proper handling via dsl file.
2987 Revision 1.54 2002/05/03 05:06:44 hal9
2988 Add brief Q/A on transparent proxies.
2990 Revision 1.53 2002/05/03 01:34:52 hal9
2991 Fix section numbering for new sections (due to TOC kludge).
2993 Revision 1.52 2002/04/29 03:08:43 hal9
2994 -Added new Q/A on new actions file set up (pointer to u-m)
2995 -Fixed a few broken links and converted old actions as a result of
2998 Revision 1.51 2002/04/26 17:24:31 swa
2999 bookmarks cleaned, changed structure of user manual, screen and programlisting cleanups, and numerous other changes that I forgot
3001 Revision 1.50 2002/04/26 05:25:23 hal9
3002 Mass commit to catch a few scattered fixes.
3004 Revision 1.49 2002/04/12 10:10:18 swa
3007 Revision 1.48 2002/04/10 18:45:15 swa
3010 Revision 1.47 2002/04/10 04:05:32 hal9
3013 Revision 1.45 2002/04/08 22:59:26 hal9
3014 Version update. Spell chkconfig correctly :)
3016 Revision 1.44 2002/04/07 21:24:29 hal9
3017 Touch up on name change.
3019 Revision 1.43 2002/04/04 21:59:53 hal9
3020 Added NT/W2K service/icon situation.
3022 Revision 1.42 2002/04/04 18:46:47 swa
3023 consistent look. reuse of copyright, history et. al.
3025 Revision 1.41 2002/04/04 06:48:37 hal9
3026 Structural changes to allow for conditional inclusion/exclusion of content
3027 based on entity toggles, e.g. 'entity % p-not-stable "INCLUDE"'. And
3028 definition of internal entities, e.g. 'entity p-version "2.9.13"' that will
3029 eventually be set by Makefile.
3030 More boilerplate text for use across multiple docs.
3032 Revision 1.40 2002/04/03 04:22:03 hal9
3033 Fixed several typos.
3035 Revision 1.39 2002/04/03 03:53:03 hal9
3036 Revert some changes, and then make some news, to layout, and appearance.
3038 Revision 1.38 2002/04/02 03:49:10 hal9
3039 Major changes to doc structure and layout. Sections are not automatically
3040 numbered now. TOC is on page by itself.
3042 Revision 1.37 2002/04/01 16:24:07 hal9
3043 -Rework of supported Q/A.
3044 -Set up entities to include boilerplate text.
3046 Revision 1.36 2002/03/31 23:18:47 hal9
3047 More on dealing with BLOCKED.
3049 Revision 1.35 2002/03/30 04:14:19 hal9
3050 Fix privoxy.org/config links.
3052 Revision 1.34 2002/03/29 04:35:56 hal9
3055 Revision 1.33 2002/03/29 01:31:48 hal9
3056 Several new Q/A's and other touch ups.
3058 Revision 1.32 2002/03/27 00:57:03 hal9
3059 Touch ups for name change.
3061 Revision 1.31 2002/03/26 22:29:55 swa
3062 we have a new homepage!
3064 Revision 1.30 2002/03/25 16:39:22 hal9
3065 A few new sections. Made all links relative to user-manual.
3067 Revision 1.29 2002/03/25 05:23:57 hal9
3068 Moved section, and touch ups.
3070 Revision 1.28 2002/03/25 04:27:33 hal9
3071 New section related to name change.
3073 Revision 1.25 2002/03/24 16:08:08 swa
3074 we are too lazy to make a block-built
3075 privoxy logo. hence removed the option.
3077 Revision 1.24 2002/03/24 15:46:20 swa
3078 name change related issue.
3080 Revision 1.23 2002/03/24 12:33:01 swa
3083 Revision 1.22 2002/03/24 11:51:00 swa
3084 name change. changed filenames.
3086 Revision 1.21 2002/03/24 11:01:06 swa
3089 Revision 1.20 2002/03/23 15:13:11 swa
3090 renamed every reference to the old name with foobar.
3091 fixed "application foobar application" tag, fixed
3092 "the foobar" with "foobar". left junkbustser in cvs
3093 comments and remarks to history untouched.
3095 Revision 1.19 2002/03/21 17:01:54 hal9
3098 Revision 1.18 2002/03/18 16:40:31 hal9
3101 Revision 1.17 2002/03/18 03:53:53 hal9
3104 Revision 1.16 2002/03/17 21:32:56 hal9
3105 A few more additions.
3107 Revision 1.15 2002/03/17 07:25:59 hal9
3108 Correcting some of my typos, and some additions.
3110 Revision 1.14 2002/03/17 02:39:13 hal9
3111 A little more added ...
3113 Revision 1.13 2002/03/17 00:22:20 hal9
3114 Adding new stuff, and trying to incorporate stuff from old faq.
3116 Revision 1.12 2002/03/11 20:13:21 swa
3119 Revision 1.11 2002/03/11 18:42:27 swa
3122 Revision 1.10 2002/03/11 13:13:27 swa
3123 correct feedback channels
3125 Revision 1.9 2002/03/10 23:34:04 swa
3126 more info on not hiding ip address
3128 Revision 1.8 2002/03/09 15:55:48 swa
3129 added default config section
3131 Revision 1.7 2002/03/07 18:16:55 swa
3134 Revision 1.6 2002/03/07 13:16:31 oes
3135 Committing changes by Stefan
3137 Revision 1.5 2002/03/02 15:50:04 swa
3138 2.9.11 version. more input for docs.
3140 Revision 1.4 2002/02/24 14:34:24 jongfoster
3141 Formatting changes. Now changing the doctype to DocBook XML 4.1
3142 will work - no other changes are needed.
3144 Revision 1.3 2001/09/23 10:13:48 swa
3145 upload process established. run make webserver and
3146 the documentation is moved to the webserver. documents
3147 are now linked correctly.
3149 Revision 1.2 2001/09/13 15:20:17 swa
3150 merged standards into developer manual
3152 Revision 1.1 2001/09/12 15:36:41 swa
3153 source files for junkbuster documentation
3155 Revision 1.3 2001/09/10 17:43:59 swa
3156 first proposal of a structure.
3158 Revision 1.2 2001/06/13 14:28:31 swa
3159 docs should have an author.
3161 Revision 1.1 2001/06/13 14:20:37 swa
3162 first import of project's documentation for the webserver.