When the Firewall service (WSPSRV.EXE) in Microsoft Forefront Threat Management Gateway 2010 reevaluates the firewall policy rules, the service may crash. If this occurs, you may find that the following event is logged in the Application log:
Log Name: Application Source: Microsoft Forefront TMG Firewall Date: datetime Event ID: 14057 Task Category: None Level: Error Keywords: Classic User: N/A Computer: Computer_Name Description: The Firewall service stopped because an application filter module C:\Program Files\Microsoft Forefront Threat Management Gateway\MSPHLPR.dll generated an exception code C0000005 in address 00000000713B893E when function CompleteAsyncIO was called. To resolve this error, remove recently installed application filters and restart the service.
This issue may occur because of a timing issue when the Firewall service processes requests.
To resolve this problem, install the hotfix package that is described in the following Microsoft Knowledge Base article:
2735208 Rollup 3 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