Assume that you run an application that is developed by using Windows Filtering Platform (WFP) API on a computer that is running Windows 7 or Windows Server 2008 R2. When the application filters network traffic, the network connection is slow.
This issue occurs because the computer does not send TCP/IP ACK messages until a time-out occurs. This occurs when the driver for WFP filters data that the driver receives through the network. Therefore, the network traffic stalls the transfer of data when the TCP/IP ACK messages are delayed.
976932 Information about Service Pack 1 for Windows 7 and for Windows Server 2008 R2
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