A known issue exists in Vista and Windows Server 2008 where use of the netsh command to change global TCP/IP settings will cause invalid values to be written into the registry under ‘HKLM\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters’. An example of this behavior is found when you run “netsh in tcp set global autotuninglevel=disabled”. Meanwhile this same key from a default installation of SBS 2008 will look similar to this. We’ve seen send/receive issues with Outlook clients as a result of this. In this case, the Exchange BPA will issue a warning if the TcpTimedWaitDelay is anything other than 60. To resolve this issue, follow links: KB967224 | Download ps1 file. And this whitepaper lists the default settings, descriptions, and valid ranges of the configurable TCP/IP registry values in Windows 2008/Vista. Refere KB951037 for information about the TCP Chimney Offload, Receive Side Scaling, and Network Direct Memory Access features in Windows Server 2008.