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+
+ <div class="SECT1">
+ <h1 class="SECT1"><a name="CONFIGURATION" id="CONFIGURATION">3.
+ Configuration</a></h1>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="AEN366" id="AEN366">3.1. What exactly is an
+ <span class="QUOTE">"actions"</span> file?</a></h3>
+
+ <p><span class="APPLICATION">Privoxy</span> utilizes the concept of
+ <span class="QUOTE">" <a href=
+ "../user-manual/actions-file.html#ACTIONS" target=
+ "_top">actions</a>"</span> that are used to manipulate and control web
+ page data. <a href="../user-manual/actions-file.html" target=
+ "_top">Actions files</a> are where these <a href=
+ "../user-manual/actions-file.html#ACTIONS" target="_top">actions</a>
+ that <span class="APPLICATION">Privoxy</span> could take while
+ processing a certain request, are configured. Typically, you would
+ define a set of default actions that apply globally to all URLs, then
+ add exceptions to these defaults where needed. There is a wide array of
+ actions available that give the user a high degree of control and
+ flexibility on how to process each and every web page.</p>
+
+ <p>Actions can be defined on a <a href=
+ "../user-manual/actions-file.html#AF-PATTERNS" target="_top">URL
+ pattern</a> basis, i.e. for single URLs, whole web sites, groups or
+ parts thereof etc. Actions can also be grouped together and then
+ applied to requests matching one or more patterns. There are many
+ possible actions that might apply to any given site. As an example, if
+ you are blocking <a href="http://en.wikipedia.org/wiki/Browser_cookie"
+ target="_top">cookies</a> as one of your default actions, but need to
+ accept cookies from a given site, you would need to define an exception
+ for this site in one of your actions files, preferably in <tt class=
+ "FILENAME">user.action</tt>.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="ACTIONSS" id="ACTIONSS">3.2. The
+ <span class="QUOTE">"actions"</span> concept confuses me. Please list
+ some of these <span class="QUOTE">"actions"</span>.</a></h3>
+
+ <p>For a comprehensive discussion of the actions concept, please refer
+ to the <a href="../user-manual/actions-file.html" target="_top">actions
+ file chapter</a> in the <a href="../user-manual/index.html" target=
+ "_top">User Manual</a>. It includes a <a href=
+ "../user-manual/actions-file.html#ACTIONS" target="_top">list of all
+ actions</a> and an <a href=
+ "../user-manual/actions-file.html#ACT-EXAMPLES" target="_top">actions
+ file tutorial</a> to get you started.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="AEN389" id="AEN389">3.3. How are actions
+ files configured? What is the easiest way to do this?</a></h3>
+
+ <p>Actions files are just text files in a special syntax and can be
+ edited with a text editor. But probably the easiest way is to access
+ <span class="APPLICATION">Privoxy</span>'s user interface with your web
+ browser at <a href="http://config.privoxy.org/" target=
+ "_top">http://config.privoxy.org/</a> (Shortcut: <a href="http://p.p/"
+ target="_top">http://p.p/</a>) and then select <span class=
+ "QUOTE">"<a href="http://config.privoxy.org/show-status" target=
+ "_top">View & change the current configuration</a>"</span> from the
+ menu. Note that this feature must be explicitly enabled in the main
+ config file (see <a href=
+ "../user-manual/config.html#ENABLE-EDIT-ACTIONS" target=
+ "_top">enable-edit-actions</a>).</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="AEN398" id="AEN398">3.4. There are several
+ different <span class="QUOTE">"actions"</span> files. What are the
+ differences?</a></h3>
+
+ <p>Please have a look at the <a href="../user-manual/actions-file.html"
+ target="_top">the actions chapter</a> in the <a href=
+ "../user-manual/index.html" target="_top">User Manual</a> for a
+ detailed explanation.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="GETUPDATES" id="GETUPDATES">3.5. Where can I
+ get updated Actions Files?</a></h3>
+
+ <p>Based on your feedback and the continuing development, updates of
+ <tt class="FILENAME">default.action</tt> will be made available from
+ time to time on the <a href=
+ "http://sourceforge.net/project/showfiles.php?group_id=11118" target=
+ "_top">files section</a> of our <a href=
+ "http://sf.net/projects/ijbswa/" target="_top">project page</a>.</p>
+
+ <p>If you wish to receive an email notification whenever we release
+ updates of <span class="APPLICATION">Privoxy</span> or the actions
+ file, <a href=
+ "http://lists.sourceforge.net/lists/listinfo/ijbswa-announce/" target=
+ "_top">subscribe to our announce mailing list</a>,
+ ijbswa-announce@lists.sourceforge.net.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="NEWCONFIG" id="NEWCONFIG">3.6. Can I use my
+ old config files?</a></h3>
+
+ <p>The syntax and purpose of configuration files has remained roughly
+ the same throughout the 3.x series, but backwards compatibility is not
+ guaranteed. Also each release contains updated, <span class=
+ "QUOTE">"improved"</span> versions and it is therefore strongly
+ recommended to install the newer configuration files and merge back
+ your modifications.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="DIFFICULT" id="DIFFICULT">3.7. Why is the
+ configuration so complicated?</a></h3>
+
+ <p><span class="QUOTE">"Complicated"</span> is in the eye of the
+ beholder. Those that are familiar with some of the underlying concepts,
+ such as regular expression syntax, take to it like a fish takes to
+ water. Also, software that tries hard to be <span class="QUOTE">"user
+ friendly"</span>, often lacks sophistication and flexibility. There is
+ always that trade-off there between power vs. easy-of-use. Furthermore,
+ anyone is welcome to contribute ideas and implementations to enhance
+ <span class="APPLICATION">Privoxy</span>.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="YAHOO" id="YAHOO">3.8. How can I make my
+ Yahoo/Hotmail/Gmail account work?</a></h3>
+
+ <p>The default configuration shouldn't impact the usability of any of
+ these services. It may, however, make all <a href=
+ "http://en.wikipedia.org/wiki/Browser_cookie" target="_top">cookies</a>
+ temporary, so that your browser will forget your login credentials in
+ between browser sessions. If you would like not to have to log in
+ manually each time you access those websites, simply turn off all
+ cookie handling for them in the <tt class="FILENAME">user.action</tt>
+ file. An example for yahoo might look like:</p>
+
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+ <pre class="SCREEN">
+# Allow all cookies for Yahoo login:
+#
+{ -<a href="../user-manual/actions-file.html#CRUNCH-INCOMING-COOKIES" target=
+"_top">crunch-incoming-cookies</a> -<a href=
+"../user-manual/actions-file.html#CRUNCH-OUTGOING-COOKIES" target=
+"_top">crunch-outgoing-cookies</a> -<a href=
+"../user-manual/actions-file.html#SESSION-COOKIES-ONLY" target=
+"_top">session-cookies-only</a> }
+.login.yahoo.com
+</pre>
+ </td>
+ </tr>
+ </table>
+
+ <p>These kinds of sites are often quite complex and heavy with <a href=
+ "http://en.wikipedia.org/wiki/Javascript" target="_top">Javascript</a>
+ and thus <span class="QUOTE">"fragile"</span>. So if <span class=
+ "emphasis"><i class="EMPHASIS">still</i></span> a problem, we have an
+ <a href="../user-manual/actions-file.html#ALIASES" target=
+ "_top">alias</a> just for such sticky situations:</p>
+
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+ <pre class="SCREEN">
+# Gmail is a _fragile_ site:
+#
+{ <tt class="LITERAL">fragile</tt> }
+ # Gmail is ...
+ mail.google.com
+</pre>
+ </td>
+ </tr>
+ </table>
+
+ <p>Be sure to flush your browser's caches whenever making these kinds
+ of changes, just to make sure the changes <span class=
+ "QUOTE">"take"</span>.</p>
+
+ <p>Make sure the domain, host and path are appropriate as well. Your
+ browser can tell you where you are specifically and you should use that
+ information for your configuration settings. Note that above it is not
+ referenced as <tt class="LITERAL">gmail.com</tt>, which is a valid
+ domain name.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="CONFIGFILES" id="CONFIGFILES">3.9. What's
+ the difference between the <span class="QUOTE">"Cautious"</span>,
+ <span class="QUOTE">"Medium"</span> and <span class=
+ "QUOTE">"Advanced"</span> defaults?</a></h3>
+
+ <p>Configuring <span class="APPLICATION">Privoxy</span> is not entirely
+ trivial. To help you get started, we provide you with three different
+ default action <span class="QUOTE">"profiles"</span> in the web based
+ actions file editor at <a href="http://config.privoxy.org/show-status"
+ target="_top">http://config.privoxy.org/show-status</a>. See the
+ <a href="../user-manual/actions-file.html" target="_top"><i class=
+ "CITETITLE">User Manual</i></a> for a list of actions, and how the
+ default profiles are set.</p>
+
+ <p>Where the defaults are likely to break some sites, exceptions for
+ known popular <span class="QUOTE">"problem"</span> sites are included,
+ but in general, the more aggressive your default settings are, the more
+ exceptions you will have to make later. New users are best to start off
+ in <span class="QUOTE">"Cautious"</span> setting. This is safest and
+ will have the fewest problems. See the <a href=
+ "../user-manual/index.html" target="_top"><i class="CITETITLE">User
+ Manual</i></a> for a more detailed discussion.</p>
+
+ <p>It should be noted that the <span class="QUOTE">"Advanced"</span>
+ profile (formerly known as the <span class=
+ "QUOTE">"Adventuresome"</span> profile) is more aggressive, and will
+ make use of some of <span class="APPLICATION">Privoxy's</span> advanced
+ features. Use at your own risk!</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="BROWSECONFIG" id="BROWSECONFIG">3.10. Why
+ can I change the configuration with a browser? Does that not raise
+ security issues?</a></h3>
+
+ <p>It may seem strange that regular users can edit the config files
+ with their browsers, although the whole <tt class=
+ "FILENAME">/etc/privoxy</tt> hierarchy belongs to the user <span class=
+ "QUOTE">"privoxy"</span>, with only 644 permissions.</p>
+
+ <p>When you use the browser-based editor, <span class=
+ "APPLICATION">Privoxy</span> itself is writing to the config files.
+ Because <span class="APPLICATION">Privoxy</span> is running as the user
+ <span class="QUOTE">"privoxy"</span>, it can update its own config
+ files.</p>
+
+ <p>If you run <span class="APPLICATION">Privoxy</span> for multiple
+ untrusted users (e.g. in a LAN) or aren't entirely in control of your
+ own browser, you will probably want to make sure that the web-based
+ editor and remote toggle features are <span class="QUOTE">"off"</span>
+ by setting <span class="QUOTE">"<tt class="LITERAL"><a href=
+ "../user-manual/config.html#ENABLE-EDIT-ACTIONS" target=
+ "_top">enable-edit-actions</a> 0</tt>"</span> and <span class=
+ "QUOTE">"<tt class="LITERAL"><a href=
+ "../user-manual/config.html#ENABLE-REMOTE-TOGGLE" target=
+ "_top">enable-remote-toggle</a> 0</tt>"</span> in the <a href=
+ "../user-manual/config.html" target="_top">main configuration
+ file</a>.</p>
+
+ <p>As of <span class="APPLICATION">Privoxy</span> 3.0.7 these options
+ are disabled by default.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="AEN486" id="AEN486">3.11. What is the
+ <tt class="FILENAME">default.filter</tt> file? What is a <span class=
+ "QUOTE">"filter"</span>?</a></h3>
+
+ <p>The <a href="../user-manual/filter-file.html" target=
+ "_top"><tt class="FILENAME">default.filter</tt></a> file is where
+ <span class="emphasis"><i class="EMPHASIS">filters</i></span> as
+ supplied by the developers are defined. Filters are a special subset of
+ actions that can be used to modify or remove web page content or
+ headers on the fly. Content filters can be applied to <span class=
+ "emphasis"><i class="EMPHASIS">anything</i></span> in the page source,
+ header filters can be applied to either server or client headers.
+ Regular expressions are used to accomplish this.</p>
+
+ <p>There are a number of pre-defined filters to deal with common
+ annoyances. The filters are only defined here, to invoke them, you need
+ to use the <a href="../user-manual/actions-file.html#FILTER" target=
+ "_top"><tt class="LITERAL">filter</tt> action</a> in one of the actions
+ files. Content filtering is automatically disabled for inappropriate
+ MIME types, but if you know better than Privoxy what should or should
+ not be filtered you can filter any content you like.</p>
+
+ <p>Filters should <span class="emphasis"><i class=
+ "EMPHASIS">not</i></span> be confused with <a href=
+ "../user-manual/actions-file.html#BLOCK" target="_top"><tt class=
+ "LITERAL">blocks</tt></a>, which is a completely different action, and
+ is more typically used to block ads and unwanted sites.</p>
+
+ <p>If you are familiar with regular expressions, and HTML, you can look
+ at the provided <tt class="FILENAME">default.filter</tt> with a text
+ editor and define your own filters. This is potentially a very powerful
+ feature, but requires some expertise in both regular expressions and
+ HTML/HTTP. You should place any modifications to the default filters,
+ or any new ones you create in a separate file, such as <tt class=
+ "FILENAME">user.filter</tt>, so they won't be overwritten during
+ upgrades. The ability to define multiple filter files in <tt class=
+ "FILENAME">config</tt> is a new feature as of v. 3.0.5.</p>
+
+ <p>There is no GUI editor option for this part of the configuration,
+ but you can disable/enable the various pre-defined filters of the
+ included <tt class="FILENAME">default.filter</tt> file with the
+ <a href="http://config.privoxy.org/show-status" target="_top">web-based
+ actions file editor</a>. Note that the custom actions editor must be
+ explicitly enabled in the main config file (see <a href=
+ "../user-manual/config.html#ENABLE-EDIT-ACTIONS" target=
+ "_top">enable-edit-actions</a>).</p>
+
+ <p>If you intend to develop your own filters, you might want to have a
+ look at <a href="http://www.fabiankeil.de/sourcecode/pft/" target=
+ "_top">Privoxy-Filter-Test</a>.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="LANCONFIG" id="LANCONFIG">3.12. How can I
+ set up Privoxy to act as a proxy for my LAN?</a></h3>
+
+ <p>By default, <span class="APPLICATION">Privoxy</span> only responds
+ to requests from <tt class="LITERAL">127.0.0.1</tt> (localhost). To
+ have it act as a server for a network, this needs to be changed in the
+ <a href="../user-manual/config.html" target="_top">main configuration
+ file</a>. Look for the <tt class="LITERAL"><a href=
+ "../user-manual/config.html#LISTEN-ADDRESS" target=
+ "_top">listen-address</a></tt> option, which may be commented out with
+ a <span class="QUOTE">"#"</span> symbol. Make sure it is uncommented,
+ and assign it the address of the LAN gateway interface, and port number
+ to use. Assuming your LAN address is 192.168.1.1 and you wish to run
+ <span class="APPLICATION">Privoxy</span> on port 8118, this line should
+ look like:</p>
+
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+ <pre class="SCREEN">
+ listen-address 192.168.1.1:8118
+</pre>
+ </td>
+ </tr>
+ </table>
+
+ <p>Save the file, and restart <span class="APPLICATION">Privoxy</span>.
+ Configure all browsers on the network then to use this address and port
+ number.</p>
+
+ <p>Alternately, you can have <span class="APPLICATION">Privoxy</span>
+ listen on all available interfaces:</p>
+
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+ <pre class="SCREEN">
+ listen-address :8118
+</pre>
+ </td>
+ </tr>
+ </table>
+
+ <p>And then use <span class="APPLICATION">Privoxy's</span> <a href=
+ "../user-manual/config.html#PERMIT-ACCESS" target=
+ "_top">permit-access</a> feature to limit connections. A firewall in
+ this situation is recommended as well.</p>
+
+ <p>The above steps should be the same for any TCP network, regardless
+ of operating system.</p>
+
+ <p>If you run <span class="APPLICATION">Privoxy</span> on a LAN with
+ untrusted users, we recommend that you double-check the <a href=
+ "../user-manual/config.html#ACCESS-CONTROL" target="_top">access
+ control and security</a> options!</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="AEN537" id="AEN537">3.13. Instead of ads,
+ now I get a checkerboard pattern. I don't want to see
+ anything.</a></h3>
+
+ <p>The replacement for blocked images can be controlled with the
+ <a href="../user-manual/actions-file.html#SET-IMAGE-BLOCKER" target=
+ "_top"><tt class="LITERAL">set-image-blocker</tt> action</a>. You have
+ the choice of a checkerboard pattern, a transparent 1x1 GIF image (aka
+ <span class="QUOTE">"blank"</span>), or a redirect to a custom image of
+ your choice. Note that this choice only has effect for images which are
+ blocked as images, i.e. whose URLs match both a <tt class=
+ "LITERAL"><a href="../user-manual/actions-file.html#HANDLE-AS-IMAGE"
+ target="_top">handle-as-image</a></tt> <span class="emphasis"><i class=
+ "EMPHASIS">and</i></span> <tt class="LITERAL"><a href=
+ "../user-manual/actions-file.html#BLOCK" target="_top">block</a></tt>
+ action.</p>
+
+ <p>If you want to see nothing, then change the <a href=
+ "../user-manual/actions-file.html#SET-IMAGE-BLOCKER" target=
+ "_top"><tt class="LITERAL">set-image-blocker</tt> action</a> to
+ <span class="QUOTE">"blank"</span>. This can be done by editing the
+ <tt class="FILENAME">user.action</tt> file, or through the <a href=
+ "http://config.privoxy.org/show-status" target="_top">web-based actions
+ file editor</a>.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="AEN554" id="AEN554">3.14. Why would anybody
+ want to see a checkerboard pattern?</a></h3>
+
+ <p>Remember that <a href="general.html#WHATSANAD">telling which image
+ is an ad and which isn't</a>, is an educated guess. While we hope that
+ the standard configuration is rather smart, it will make occasional
+ mistakes. The checkerboard image is visually decent, and it shows you
+ where images have been blocked, which can be very helpful in case some
+ navigation aid or otherwise innocent image was erroneously blocked. It
+ is recommended for new users so they can <span class=
+ "QUOTE">"see"</span> what is happening. Some people might also enjoy
+ seeing how many banners they <span class="emphasis"><i class=
+ "EMPHASIS">don't</i></span> have to see.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="AEN560" id="AEN560">3.15. I see some images
+ being replaced with text instead of the checkerboard image. Why and how
+ do I get rid of this?</a></h3>
+
+ <p>This happens when the banners are not embedded in the HTML code of
+ the page itself, but in separate HTML (sub)documents that are loaded
+ into (i)frames or (i)layers, and these external HTML documents are
+ blocked. Being non-images they get replaced by a substitute HTML page
+ rather than a substitute image, which wouldn't work out technically,
+ since the browser expects and accepts only HTML when it has requested
+ an HTML document.</p>
+
+ <p>The substitute page adapts to the available space and shows itself
+ as a miniature two-liner if loaded into small frames, or full-blown
+ with a large red "BLOCKED" banner if space allows.</p>
+
+ <p>If you prefer the banners to be blocked by images, you must see to
+ it that the HTML documents in which they are embedded are not blocked.
+ Clicking the <span class="QUOTE">"See why"</span> link offered in the
+ substitute page will show you which rule blocked the page. After
+ changing the rule and un-blocking the HTML documents, the browser will
+ try to load the actual banner images and the usual image blocking will
+ (hopefully!) kick in.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="SRVANY" id="SRVANY">3.16. Can Privoxy run as
+ a service on Win2K/NT/XP?</a></h3>
+
+ <p>Yes. Version 3.0.5 introduces full <span class=
+ "APPLICATION">Windows</span> service functionality. See <a href=
+ "../user-manual/installation.html#installation-pack-win" target=
+ "_top">the <i class="CITETITLE">User Manual</i></a> for details on how
+ to install and configure <span class="APPLICATION">Privoxy</span> as a
+ service.</p>
+
+ <p>Earlier 3.x versions could run as a system service using <b class=
+ "COMMAND">srvany.exe</b>. See the discussion at <a href=
+ "http://sourceforge.net/tracker/?func=detail&atid=361118&aid=485617&group_id=11118"
+ target=
+ "_top">http://sourceforge.net/tracker/?func=detail&atid=361118&aid=485617&group_id=11118</a>,
+ for details, and a sample configuration.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="OTHERPROXY" id="OTHERPROXY">3.17. How can I
+ make Privoxy work with other proxies?</a></h3>
+
+ <p>This can be done and is often useful to combine the benefits of
+ <span class="APPLICATION">Privoxy</span> with those of a another proxy,
+ for example to cache content. See the <a href=
+ "../user-manual/config.html#FORWARDING" target="_top">forwarding
+ chapter</a> in the <a href="../user-manual/index.html" target=
+ "_top">User Manual</a> which describes how to do this. If you intend to
+ use Privoxy with Tor, please also have a look at <a href=
+ "misc.html#TOR">How do I use Privoxy together with Tor</a>.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="PORT-80" id="PORT-80">3.18. Can I just set
+ Privoxy to use port 80 and thus avoid individual browser
+ configuration?</a></h3>
+
+ <p>No, its more complicated than that. This only works with special
+ kinds of proxies known as <span class="QUOTE">"intercepting"</span>
+ proxies (<a href="configuration.html#INTERCEPTING">see below</a>).</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="TRANSPARENT" id="TRANSPARENT">3.19. Can
+ Privoxy run as a <span class="QUOTE">"transparent"</span>
+ proxy?</a></h3>
+
+ <p>The whole idea of Privoxy is to modify client requests and server
+ responses in all sorts of ways and therefore it's not a transparent
+ proxy as described in <a href="http://tools.ietf.org/html/rfc2616"
+ target="_top">RFC 2616</a>.</p>
+
+ <p>However, some people say <span class="QUOTE">"transparent
+ proxy"</span> when they mean <span class="QUOTE">"intercepting
+ proxy"</span>. If you are one of them, please read the <a href=
+ "configuration.html#INTERCEPTING">next entry</a>.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="INTERCEPTING" id="INTERCEPTING">3.20. Can
+ Privoxy run as a <span class="QUOTE">"intercepting"</span>
+ proxy?</a></h3>
+
+ <p><span class="APPLICATION">Privoxy</span> can't intercept traffic
+ itself, but it can handle requests that where intercepted and
+ redirected with a packet filter (like <span class=
+ "APPLICATION">PF</span> or <span class="APPLICATION">iptables</span>),
+ as long as the <tt class="LITERAL">Host</tt> header is present.</p>
+
+ <p>As the <tt class="LITERAL">Host</tt> header is required by HTTP/1.1
+ and as most web sites rely on it anyway, this limitation shouldn't be a
+ problem.</p>
+
+ <p>Please refer to your packet filter's documentation to learn how to
+ intercept and redirect traffic into <span class=
+ "APPLICATION">Privoxy</span>. Afterward you just have to configure
+ <span class="APPLICATION">Privoxy</span> to <a href=
+ "../user-manual/config.html#ACCEPT-INTERCEPTED-REQUESTS" target=
+ "_top">accept intercepted requests</a>.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="OUTLOOK" id="OUTLOOK">3.21. How can I
+ configure Privoxy for use with Outlook?</a></h3>
+
+ <p>Versions of <span class="APPLICATION">Outlook</span> prior to Office
+ 2007, use <span class="APPLICATION">Internet Explorer</span> components
+ to both render HTML, and fetch any HTTP requests that may be embedded
+ in an HTML email. So however you have <span class=
+ "APPLICATION">Privoxy</span> configured to work with IE, this
+ configuration should automatically be shared, at least with older
+ version of Internet Explorer.</p>
+
+ <p>Starting with Office 2007, Microsoft is instead using the MS-Word
+ rendering engine with Outlook. It is unknown whether this can be
+ configured to use a proxy.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="OUTLOOK-MORE" id="OUTLOOK-MORE">3.22. How
+ can I have separate rules just for HTML mail?</a></h3>
+
+ <p>The short answer is, you can't. <span class=
+ "APPLICATION">Privoxy</span> has no way of knowing which particular
+ application makes a request, so there is no way to distinguish between
+ web pages and HTML mail. <span class="APPLICATION">Privoxy</span> just
+ blindly proxies all requests. In the case of <span class=
+ "APPLICATION">Outlook Express</span> (see above), OE uses IE anyway,
+ and there is no way for <span class="APPLICATION">Privoxy</span> to
+ ever be able to distinguish between them (nor could any other proxy
+ type application for that matter).</p>
+
+ <p>For a good discussion of some of the issues involved (including
+ privacy and security issues), see <a href=
+ "http://sourceforge.net/tracker/?func=detail&atid=211118&aid=629518&group_id=11118"
+ target=
+ "_top">http://sourceforge.net/tracker/?func=detail&atid=211118&aid=629518&group_id=11118</a>.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="SNEAKY-COOKIES" id="SNEAKY-COOKIES">3.23. I
+ sometimes notice cookies sneaking through. How?</a></h3>
+
+ <p><a href="http://en.wikipedia.org/wiki/Browser_cookie" target=
+ "_top">Cookies</a> can be set in several ways. The classic method is
+ via the <tt class="LITERAL">Set-Cookie</tt> HTTP header. This is
+ straightforward, and an easy one to manipulate, such as the
+ <span class="APPLICATION">Privoxy</span> concept of <a href=
+ "../user-manual/actions-file.html#SESSION-COOKIES-ONLY" target=
+ "_top">session-cookies-only</a>. There is also the possibility of using
+ <a href="http://en.wikipedia.org/wiki/Javascript" target=
+ "_top">Javascript</a> to set cookies (<span class=
+ "APPLICATION">Privoxy</span> calls these <tt class=
+ "LITERAL">content-cookies</tt>). This is trickier because the syntax
+ can vary widely, and thus requires a certain amount of guesswork. It is
+ not realistic to catch all of these short of disabling Javascript,
+ which would break many sites. And lastly, if the cookies are embedded
+ in a HTTPS/SSL secure session via Javascript, they are beyond
+ <span class="APPLICATION">Privoxy's</span> reach.</p>
+
+ <p>All in all, <span class="APPLICATION">Privoxy</span> can help manage
+ cookies in general, can help minimize the loss of privacy posed by
+ cookies, but can't realistically stop all cookies.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="EVIL-COOKIES" id="EVIL-COOKIES">3.24. Are
+ all cookies bad? Why?</a></h3>
+
+ <p>No, in fact there are many beneficial uses of <a href=
+ "http://en.wikipedia.org/wiki/Browser_cookie" target=
+ "_top">cookies</a>. Cookies are just a method that browsers can use to
+ store data between pages, or between browser sessions. Sometimes there
+ is a good reason for this, and the user's life is a bit easier as a
+ result. But there is a long history of some websites taking advantage
+ of this layer of trust, and using the data they glean from you and your
+ browsing habits for their own purposes, and maybe to your potential
+ detriment. Such sites are using you and storing their data on your
+ system. That is why the privacy conscious watch from whom those cookies
+ come, and why they really <span class="emphasis"><i class=
+ "EMPHASIS">need</i></span> to be there.</p>
+
+ <p>See the <a href="http://en.wikipedia.org/wiki/Browser_cookie"
+ target="_top">Wikipedia cookie definition</a> for more.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="ALLOW-COOKIES" id="ALLOW-COOKIES">3.25. How
+ can I allow permanent cookies for my trusted sites?</a></h3>
+
+ <p>There are several actions that relate to cookies. The default
+ behavior is to allow only <span class="QUOTE">"session cookies"</span>,
+ which means the cookies only last for the current browser session. This
+ eliminates most kinds of abuse related to cookies. But there may be
+ cases where you want cookies to last.</p>
+
+ <p>To disable all cookie actions, so that cookies are allowed
+ unrestricted, both in and out, for <tt class=
+ "LITERAL">example.com</tt>:</p>
+
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+ <pre class="SCREEN">
+ { -crunch-incoming-cookies -crunch-outgoing-cookies -session-cookies-only -filter{content-cookies} }
+ .example.com
+</pre>
+ </td>
+ </tr>
+ </table>
+
+ <p>Place the above in <tt class="FILENAME">user.action</tt>. Note that
+ some of these may be off by default anyway, so this might be redundant,
+ but there is no harm being explicit in what you want to happen.
+ <tt class="FILENAME">user.action</tt> includes an alias for this
+ situation, called <tt class="LITERAL">allow-all-cookies</tt>.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="MULTIPLES" id="MULTIPLES">3.26. Can I have
+ separate configurations for different users?</a></h3>
+
+ <p>Each instance of <span class="APPLICATION">Privoxy</span> has its
+ own configuration, including such attributes as the TCP port that it
+ listens on. What you can do is run multiple instances of <span class=
+ "APPLICATION">Privoxy</span>, each with a unique <a href=
+ "../user-manual/config.html#LISTEN-ADDRESS" target=
+ "_top">listen-address</a> configuration setting, and configuration
+ path, and then each of these can have their own configurations. Think
+ of it as per-port configuration.</p>
+
+ <p>Simple enough for a few users, but for large installations, consider
+ having groups of users that might share like configurations.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="WHITELISTS" id="WHITELISTS">3.27. Can I
+ set-up Privoxy as a whitelist of <span class="QUOTE">"good"</span>
+ sites?</a></h3>
+
+ <p>Sure. There are a couple of things you can do for simple
+ white-listing. Here's one real easy one:</p>
+
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+ <pre class="SCREEN">
+ ############################################################
+ # Blacklist
+ ############################################################
+ { <a href="../user-manual/actions-file.html#BLOCK" target=
+"_top">+block</a> }
+ / # Block *all* URLs
+
+ ############################################################
+ # Whitelist
+ ############################################################
+ { <a href="../user-manual/actions-file.html#BLOCK" target=
+"_top">-block</a> }
+ kids.example.com
+ toys.example.com
+ games.example.com
+</pre>
+ </td>
+ </tr>
+ </table>
+
+ <p>This allows access to only those three sites by first blocking all
+ URLs, and then subsequently allowing three specific exceptions.</p>
+
+ <p>Another approach is <span class="APPLICATION">Privoxy's</span>
+ <tt class="LITERAL">trustfile</tt> concept, which incorporates the
+ notion of <span class="QUOTE">"trusted referrers"</span>. See the
+ <a href="../user-manual/config.html#TRUSTFILE" target="_top">Trust
+ documentation</a> for details.</p>
+
+ <p>These are fairly simple approaches and are not completely foolproof.
+ There are various other configuration options that should be disabled
+ (described elsewhere here and in <a href="../user-manual/" target=
+ "_top">the User Manual</a>) so that users can't modify their own
+ configuration and easily circumvent the whitelist.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="NO-ADBLOCK" id="NO-ADBLOCK">3.28. How can I
+ turn off ad-blocking?</a></h3>
+
+ <p>Ad blocking is achieved through a complex application of various
+ <span class="APPLICATION">Privoxy</span> <a href=
+ "../user-manual/actions-file.html" target="_top">actions</a>. These
+ actions are deployed against simple images, banners, flash animations,
+ text pages, JavaScript, pop-ups and pop-unders, etc., so its not as
+ simple as just turning one or two actions off. The various actions that
+ make up <span class="APPLICATION">Privoxy</span> ad blocking are
+ hard-coded into the default configuration files. It has been assumed
+ that everyone using <span class="APPLICATION">Privoxy</span> is
+ interested in this particular feature.</p>
+
+ <p>If you want to do without this, there are several approaches you can
+ take: You can manually undo the many block rules in <tt class=
+ "FILENAME">default.action</tt>. Or even easier, just create your own
+ <tt class="FILENAME">default.action</tt> file from scratch without the
+ many ad blocking rules, and corresponding exceptions. Or lastly, if you
+ are not concerned about the additional blocks that are done for privacy
+ reasons, you can very easily over-ride <span class="emphasis"><i class=
+ "EMPHASIS">all</i></span> blocking with the following very simple rule
+ in your <tt class="FILENAME">user.action</tt>:</p>
+
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+ <pre class="SCREEN">
+ # Unblock everybody, everywhere
+ { <a href="../user-manual/actions-file.html#BLOCK" target=
+"_top">-block</a> }
+ / # UN-Block *all* URLs
+</pre>
+ </td>
+ </tr>
+ </table>
+
+ <p>Or even a more comprehensive reversing of various ad related
+ actions:</p>
+
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+ <pre class="SCREEN">
+ # Unblock everybody, everywhere, and turn off appropriate filtering, etc
+ { <a href="../user-manual/actions-file.html#BLOCK" target=
+"_top">-block</a> \
+ <a href="../user-manual/actions-file.html#FILTER-BANNERS-BY-SIZE" target=
+"_top">-filter{banners-by-size}</a> \
+ <a href="../user-manual/actions-file.html#FILTER-BANNERS-BY-LINK" target=
+"_top">-filter{banners-by-link}</a> \
+ <tt class="LITERAL">allow-popups</tt> \
+ }
+ / # UN-Block *all* URLs and allow ads
+</pre>
+ </td>
+ </tr>
+ </table>
+
+ <p>This last <span class="QUOTE">"action"</span> in this compound
+ statement, <tt class="LITERAL">allow-popups</tt>, is an <a href=
+ "../user-manual/actions-file.html#ALIASES" target="_top">alias</a> that
+ disables various pop-up blocking features.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="TEMPLATES" id="TEMPLATES">3.29. How can I
+ have custom template pages, like the <span class="emphasis"><i class=
+ "EMPHASIS">BLOCKED</i></span> page?</a></h3>
+
+ <p><span class="APPLICATION">Privoxy</span> <span class=
+ "QUOTE">"templates"</span> are specialized text files utilized by
+ <span class="APPLICATION">Privoxy</span> for various purposes and can
+ easily be modified using any text editor. All the template pages are
+ installed in a sub-directory appropriately named: <tt class=
+ "FILENAME">templates</tt>. Knowing something about HTML syntax will of
+ course be helpful.</p>
+
+ <p>Be forewarned that the default templates are subject to being
+ overwritten during upgrades. You can, however, create completely new
+ templates, place them in another directory and specify the alternate
+ path in the main <tt class="FILENAME">config</tt>. For details, have a
+ look at the <a href="../user-manual/config.html#templdir" target=
+ "_top">templdir</a> option.</p>
+ </div>
+
+ <div class="SECT2">
+ <h3 class="SECT2"><a name="BLOCKALL" id="BLOCKALL">3.30. How can I
+ remove the <span class="QUOTE">"Go There Anyway"</span> link from the
+ <span class="emphasis"><i class="EMPHASIS">BLOCKED</i></span>
+ page?</a></h3>
+
+ <p>There is more than one way to do it (although Perl is not
+ involved).</p>
+
+ <p>Editing the BLOCKED template page (see above) may dissuade some
+ users, but this method is easily circumvented. Where you need this
+ level of control, you might want to build <span class=
+ "APPLICATION">Privoxy</span> from source, and disable various features
+ that are available as compile-time options. You should <b class=
+ "COMMAND">configure</b> the sources as follows:</p>
+
+ <table border="0" bgcolor="#E0E0E0" width="100%">
+ <tr>
+ <td>
+ <pre class="SCREEN">
+ ./configure --disable-toggle --disable-editor --disable-force
+</pre>
+ </td>
+ </tr>
+ </table>
+
+ <p>This will create an executable with hard-coded security features so
+ that <span class="APPLICATION">Privoxy</span> does not allow easy
+ bypassing of blocked sites, or changing the current configuration via
+ any connected user's web browser.</p>
+
+ <p>Finally, all of these features can also be toggled on/off via
+ options in <span class="APPLICATION">Privoxy's</span> main <a href=
+ "../user-manual/config.html#ACCESS-CONTROL" target="_top">config</a>
+ file which means you don't have to recompile anything.</p>
+ </div>
+ </div>
+
+ <div class="NAVFOOTER">
+ <hr align="left" width="100%">
+
+ <table summary="Footer navigation table" width="100%" border="0"
+ cellpadding="0" cellspacing="0">
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+
+ <td width="34%" align="center" valign="top"><a href="index.html"
+ accesskey="H">Home</a></td>
+
+ <td width="33%" align="right" valign="top"><a href="misc.html"
+ accesskey="N">Next</a></td>
+ </tr>
+
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+ <td width="33%" align="left" valign="top">Installation</td>
+
+ <td width="34%" align="center" valign="top"> </td>
+
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+ </table>
+ </div>
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