Event ID 2020 error messages are logged in the System log, and you experience decreased performance on a server that is running Windows Server 2003 or Windows 2000,

You experience decreased performance on a computer that is running Microsoft Windows Server 2003 or Microsoft Windows 2000. The computer may eventually stop responding (hang). Additionally, you experience the following symptoms:

�	Event ID error messages that resemble the following are logged in the System log: Event ID 2020 Type: Error Source: Srv Description: The server was unable to allocate from the system paged pool because the pool was empty.
�	The Memory Pool Monitor (Poolmon.exe) tool shows high usage of the MmST tag.

This problem occurs if a memory leak occurs, and then paged pool memory is exhausted.

Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall the operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.

To help resolve this issue, modify the registry to configure the following tuning changes to the computer:

�	Throttle the Server service.
�	Maximize the total amount of available paged pool memory.
�	Prevent the computer from using all available physical memory for file caching.
�	Prevent stale network connections to the server from using resources.

To do this, follow these steps:

1.	Click Start, click Run, type regedit, and then click OK. Note The remaining steps describe how to add registry entries and then how to set the registry entries to a specific value. Create the registry entries only if they do not already exist on the computer. If the registry entries already exist, set the entry to the appropriate value.
2.	Throttle the Server service by configuring the MaxMpxCt, SizReqBuf, and Autodisconnect registry entries in the following registry subkey: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\lanmanserver\Parameters To do this, follow these steps: a. Locate and then click the following registry subkey: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\lanmanserver\Parameters b. On the Edit menu, point to New, and then click DWORD Value. c. Type MaxMpxCt, and then press ENTER. d. Double-click MaxMpxCt, click Hexadecimal, type 0000000A in the Value data box, and then click OK. e. On the Edit menu, point to New, and then click DWORD Value. f. Type SizReqBuf, and then press ENTER. g. Double-click SizReqBuf, click Hexadecimal, type 00001000 in the Value data box, and then click OK. h. On the Edit menu, point to New, and then click DWORD Value. i. Type Autodisconnect, and then press ENTER. j. Double-click Autodisconnect, click Hexadecimal, type 00000000 in the Value data box, and then click OK.
3.	Maximize the total amount of available paged pool memory, and prevent the computer from using all available physical memory for file caching. To do this, configure the PoolUsageMaximum, PagedPoolSize, and LargeSystemCache registry entries in the following registry subkey: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\Memory Management To do this, follow these steps: a. Locate and then click the following registry subkey HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\Memory Management b. On the Edit menu, point to New, and then click DWORD Value. c. Type PoolUsageMaximum, and then press ENTER. d. Double-click PoolUsageMaximum, click Hexadecimal, type 00000028 in the Value data box, and then click OK. e. Double-click PagedPoolSize, click Hexadecimal, type ffffffff in the Value data box, and then click OK. f. On the Edit menu, point to New, and then click DWORD Value. g. Type LargeSystemCache, and then press ENTER. h. Double-click LargeSystemCache, click Hexadecimal, type 00000000 in the Value data box, and then click OK.
4.	Prevent stale network connections to the server from using resources by configuring the TcpTimedWaitDelay registry entry in the following registry subkey: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters To do this, follow these steps: a. Locate and then click the following registry subkey: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters b. On the Edit menu, point to New, and then click DWORD Value. c. Type TcpTimedWaitDelay, and then press ENTER. d. Double-click TcpTimedWaitDelay, click Hexadecimal, type 0000001e in the Value data box, and then click OK.

For more information about how to troubleshoot issues in which event ID 2020 error messages are logged in the System log, click the following article numbers to view the articles in the Microsoft Knowledge Base: