Recommended settings for Internet Explorer when using Guardian web filter

Article #: Product Castle
1665 Guardian All


A how to guide to setting up the ideal settings for the Guardian web filter in Internet Explorer


Recommended settings for Internet Explorer when using Guardian web filter


When using Internet Explorer (any version) with the Guardian web filter it is recommended to implement the group policy setting detailed in the Microsoft Knowledge base article 271361. As mentioned in the knowledge base article, there are two ways to implement this setting.

Method 1: Modify the registry

You can disable the Automatic Proxy Result Cache by using the following registry key:

HKEY_CURRENT_USER\Software\Policies\Microsoft\Windows\CurrentVersion\Internet Settings

  • Value: EnableAutoproxyResultCache
  • Type: REG_DWORD
  • Data value: 0 = disable caching; 1 (or key not present) = enable automatic proxy caching (this is the default behavior)

If the registry key is not present, you can create the registry key by using the following registry file:

Windows Registry Editor Version 5.00 [HKEY_CURRENT_USER\Software\Policies\Microsoft\Windows\CurrentVersion\Internet Settings]

  • EnableAutoProxyResultCache"=dword:00000000"

Method 2: Modify Group Policy settings

  1. Click Start
  2. Click Run
  3. Type gpedit.msc, and then click OK
  4. In Group Policy Object Editor, double-click User Configuration > Administrative Templates > Windows Components > Internet Explorer
  5. Double-click Disable caching of Auto-Proxy scripts
  6. Click Enable, and then click OK.

The final paragraph of the knowledge base article states that: "You may have to use this registry key if you connect by using a proxy server that is handling secure and non-secure requests on the same server. One example of this behavior is the SQUID Proxy Server software. Because Internet Explorer typically caches port information, it may not send a secure request over the correct port number when it tries to send secure and non-secure responses to the same server, but on different port numbers." The Guardian web filter does use the Squid proxy software.


Last updated: Author: Contributions by:
07 September 2016   DMT