In a Microsoft Forefront Threat Management Gateway 2010 (TMG) environment, the Firewall service (Wspsrv.exe) in Forefront TMG may intermittently crash when it processes client web proxy requests. When this problem occurs, you may find that the following event is logged in the System log:
To resolve this problem, install the hotfix package that is described in the following Microsoft Knowledge Base article:
2689195 Rollup 2 for Forefront Threat Management Gateway (TMG) 2010 Service Pack 2
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base:
824684 Description of the standard terminology that is used to describe Microsoft software updates
Article ID: 2705787 - Last Review: May 4, 2012 - Revision: 1
Microsoft Forefront Threat Management Gateway 2010 Service Pack 2, Microsoft Forefront Threat Management Gateway 2010 Enterprise, Microsoft Forefront Threat Management Gateway 2010 Standard