Symptoms
The Firewall service (Wspsrv.exe) in Microsoft Threat Management Gateway (TMG) 2010 may crash intermittently when the DiffServ filter is enabled.
Resolution
To resolve this problem, install Rollup 5 for Forefront Threat Management Gateway 2010 Service Pack 2.
Workaround
To work around this problem, disable the DiffServ filter at the array level.
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.