Article ID: 2551554 - View products that this article applies to.
In very rare scenarios, it is possible for certain server connection errors to result in proxy servers being added to the bad proxy list incorrectly, causing Internet Explorer to rotate through the specified list of proxy servers until all are temporarily disabled. At this point, Internet Explorer will show a “Page Cannot be Displayed” error until the bad proxy list is cleared (30 minutes later by default).
For performance reasons, in the event that Internet Explorer cannot establish a connection to a proxy server, that proxy server is added to a list of bad proxy servers so that it is not reused for a period of time. This period of time is 30 minutes by default. If an automatic proxy configuration script returns a PROXY list that specifies multiple proxy servers, a connection to the next proxy in the list will be attempted. If that connection fails, then the process repeats until a connection is established or the list is exhausted. If the list is exhausted and no connection was established, the user will receive a "Page Cannot Be Displayed" error message in Internet Explorer.
Microsoft is investigating the issue and available options. If you encounter this issue, there are temporary workarounds that can restore connectivity.
The following workarounds are available:
Restart Internet Explorer to clear the list of bad proxy servers.
Warning: Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall the operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.
To have us fix this problem for you, go to the "Fix it for me" section. If you prefer to fix this problem yourself, go to the "Let me fix it myself" section.
Fix it for me
To fix this problem automatically, click the Fix it button or link. Then click Run in the File Download dialog box, and follow the steps in the Fix it wizard.
Fix this problem
Microsoft Fix it 50746
Then, go to the "Did this fix the problem?" section.
Let me fix it myselfSet a custom-retry interval for bad proxy servers under the following registry key:
Create a DWORD value in this key named BadProxyExpiresTime, and assign a value of 0. Note that this value is in seconds.
Setting this value to 0 will prevent proxy servers from being added to the bad proxy list.
Did this fix the problem?
BadProxyExpiresTime was introduced with Internet Explorer 5.01. For more information, please see the following:
Internet Explorer does not retry bad proxy server for 30 minutes