FIX: "Your client does not support opening this list with Windows Explorer" error when you try to open a SharePoint document library

Symptoms

Consider the following scenario:

• You publish a Microsoft SharePoint application to a trunk in Microsoft Forefront Unified Access Gateway 2010 Service Pack 4.

• You access the document library for the application and then select the Open with Explorer option.

In this scenario, the SharePoint document library does not open. Additionally, you receive the following error message:

Note This problem can occur when the following conditions are true:

• The client-side computer clock time is ahead of the UAG clock time.

• The Office persistent cookies that are issued by Forefront Unified Access Gateway are expired as per the client-side computer clock time.

Resolution

This problem is fixed in Rollup 1 for Forefront Unified Access Gateway 2010 Service Pack 4.

After you apply Rollup 1, follow these steps:

1. Create the following registry subkey:
   
   

   Subkey: HKEY_LOCAL_MACHINE\Software\WhaleCom\e-Gap\Von\UrlFilter
   Name: PersistForOfficeCookieExpirationTime
   Type: REG_DWORD
   Value: 60 - 600 (decimal)Note The default value is 60 seconds, and the maximum permitted limit is 600 seconds.
   
   

2. Enable the configuration in the Forefront Unified Access Gateway Management console.

3. Restart the Internet Information Services (IIS) service on the Forefront Unified Access Gateway servers.

Status

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

References

Learn about the terminology that Microsoft uses to describe software updates.