Error Message: Error 12206. The Proxy Server Detected Proxy Chain Loop. Please Contact Your Server... (278032)


The information in this article applies to:

  • Microsoft Proxy Server 2.0
This article was previously published under Q278032

SYMPTOMS

Microsoft Internet Explorer that is using Microsoft Proxy Server Service Pack 1 (SP1) may generate the following error message:
Error 12206. The Proxy server detected proxy chain loop. Please contact your server administrator.

CAUSE

This problem can occur because some Internet Web servers may incorrectly return the proxy server's own hostname in the VIA HTTP header. Although this problem should be corrected on the source Web server, this response will also cause an incorrect Proxy Chain Loop error.

RESOLUTION

A supported fix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Apply it only to computers that are experiencing this specific problem. This fix may receive additional testing. Therefore, if you are not severely affected by this problem, Microsoft recommends that you wait for the next Proxy Server service pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information about support costs, visit the following Microsoft Web site:

http://support.microsoft.com/default.aspx?scid=fh;EN-US;CNTACTMS

NOTE: In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The typical support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

The English version of this fix should have the following file attributes or later:
   Date      Time    Version      Size     File name     Platform
   --------------------------------------------------------------
   12/15/00  04:10p  2.0.390.16   190,224  W3proxy.dll   x86

WORKAROUND

To work around this problem, note that this problem does not occur on a non-Proxy Server SP1 computer, so you can remove SP1 to work around this problem.

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.

MORE INFORMATION

The error message that is listed in the "Symptoms" section of this article could be correct if you have not correctly configured Proxy Array. You can verify the VIA Hostname problem by running a network trace. If you see the Proxy server's own name in the VIA field that has been returned by the target Web server, you should apply this hotfix.
Modification Type:MinorLast Reviewed:10/7/2005
Keywords:kbHotfixServer kbQFE kbenv kberrmsg kbfix kbprb kbQFE KB278032
©2004 Microsoft Corporation. All rights reserved.