Scalable Networking Pack Update is Available

[This topic is intended to address a specific issue called out by the Exchange Server Analyzer Tool. You should apply it only to systems that have had the Exchange Server Analyzer Tool run against them and are experiencing that specific issue. The Exchange Server Analyzer Tool, available as a free download, remotely collects configuration data from each server in the topology and automatically analyzes the data. The resulting report details important configuration issues, potential problems, and nondefault product settings. By following these recommendations, you can achieve better performance, scalability, reliability, and uptime. For more information about the tool or to download the latest versions, see "Microsoft Exchange Analyzers" at]  

Topic Last Modified: 2008-11-13

The Microsoft Exchange Analyzer Tool examines the following registry entry to determine the version of the Microsoft Windows operating system that is running on the computer:

HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\CurrentVersion

Version values are as follows:

CurrentVersion value Microsoft Windows operating system


Microsoft Windows NT® Server 4.0


Microsoft Windows 2000 Server


Microsoft Windows Server™ 2003


Microsoft Windows Server 2008

Next, the Exchange Analyzer queries the Win32_OperatingSystem Windows Management Instrumentation (WMI) class to determine the value for the ServicePackMajorVersion key. The value for the ServicePackMajorVersion key indicates which Windows service pack is installed on the computer.

Finally, the Exchange Analyzer queries the CIM_Datafile Microsoft Windows® Management Instrumentation (WMI) class to determine the value that is set for the Version key of the Tcpip.sys file.

If the Exchange Analyzer determines that all of the following conditions are true, the Exchange Analyzer displays an error message:

  • The target computer is running on the Windows Server 2003 operating system with Windows Server 2003 Service Pack 2 (SP2) installed.

  • The Tcpip.sys file on the target computer is older than version 5.2.3790.4331.

This error means that there is a Scalable Networking Pack (SNP) rollup hotfix package available for this computer that may address possible networking issues for this computer in some configurations.

Symptoms of these networking issues may include, but are not limited to the following:

  • Connection to the server using a VPN connection fails with the error message "Error 800: Unable to establish connection."

  • Remote Desktop Protocol (RDP) connections to the server cannot be created.

  • Computers on the same local area network cannot connect to shares on the server.

  • Microsoft Office Outlook clients cannot connect to the Exchange server.

  • Generally slow network performance.

  • Outgoing FTP connections cannot be established from the server.

  • Network Address Translation (NAT) clients that are located behind Windows Small Business Server 2003 or Internet Security and Acceleration (ISA) Server experience intermittent connection failures.

  • Intermittent RPC communications failures.

  • The server stops responding.

To help address some of the symptoms listed above that might be affecting your server, download and install the SNP hotfix rollup package described in Microsoft Knowledge Base article 950224, "A Scalable Networking Pack (SNP) hotfix rollup package is available for Windows Server 2003" (

For more information about this issue, see the following Exchange resources:

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