After you install Windows Server 2003 Service Pack 2 (SP2)
or Windows Server 2003 Scalable Networking Pack (SNP) on a computer that has a
TCP/IP Offload-enabled network adapter, you may experience many network-related
The following issues may occur when Windows Server 2003 SNP is turned on:
To work around this problem, use any of the following three methods. You must restart the computer after you try any of these methods.
Method 1: Manually disable Receive Side Scaling and TCP Offload in the network adapter driver
Method 2: Update the network adapter drivers
Method 3: Manually disable RSS and TCP Offload in the registry
Check whether the problem is fixed. If it is fixed, you are finished with this article. If it is not fixed, you can contact support. To do this, go to the Microsoft Support for small business
has confirmed that this is a problem in the Microsoft products that are listed
in the "Applies to" section.
These issues occur because of several problems with the Windows Server 2003 SNP features that are enabled in Windows Server 2003 Service Pack 2. These features include Receive Side Scaling (RSS) and TCP/IP
Offloading. Specifically, these problems include the following:
- RSS is incompatible with NAT or with Network Load Balancing (NLB).
- TCP/IP Offload has a problem with the Window Scaling feature. This problem typically occurs when you communicate with a Windows Vista-based computer. Windows Vista uses the Window Scaling feature.
- Some TCP/IP Offload-enabled network adapters do not send TCP keep-alive messages but Exchange servers use TCP keep-alive messages to clean up inactive client sessions.
- The TCP/IP Offload-enabled network adapter may consume lots of nonpaged pool memory. This may cause other problems in the operating system.
- In some cases, the TCP/IP Offload-enabled network adapter may request large blocks of contiguous memory. This makes the computer crash when it tries to free the memory.
For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base:
Description of the standard terminology that is used to describe Microsoft software updates
For more information about SNP, click the following article number to view the article in the Microsoft Knowledge Base:
The Microsoft Windows Server 2003 Scalable Networking Pack release
In rare cases, this hotfix does not work. For example, when you use network adapter teaming software on the computer, the changes to TCP Chimney and RSS settings are not picked up by the network adapter teaming software. This causes a loss of network connectivity. After you apply this hotfix, you must verify the properties of the network adapter team to make sure that the TCP Chimney or TOE and RSS settings have also been disabled. If the hotfix cannot disable the TCP Chimney or TOE and RSS feature, you can manually disable RSS and TCP Chimney Offload by using one of the methods that is mentioned in the Workaround section.
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