To resolve this issue, install the software update that is described in the following Microsoft Knowledge Base (KB) article:
2475183 Software Update 1 rollup 2 for Forefront Threat Management Gateway (TMG) 2010 Service Pack 1
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
If you do not configure the following registry subkeys, and if you do not install this hotfix, the default value of the subkeys is 4. After you apply this hotfix, the default value for these subkeys is 16.
To optimize the bandwidth of the Internet connection, you may have to change the value of TcpBufferSize by using the following script: