MTA event ID 57 on bridgehead servers

You may see slow mail flow on message transfer agent (MTA) or connector bridgehead servers. In addition, you may see the following event logged in the Application event log:

WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

To improve the performance on the bridgehead servers, change the entries in this registry key to a value of 6.

Note You can use a value of 6 for single processor servers. And, you can use a value of 8 for multiprocessor servers.

For more information, click the following article numbers to view the articles in the Microsoft Knowledge Base:
To do this, follow these steps:

1. Start Registry Editor (Regedt32.exe).
2. Locate the Dispatcher threads, Kernel threads, RTS threads, and Transfer threads values under the following key in the registry:
   HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeMTA\Parameters
   NOTE: The above registry key is one path; it has been wrapped for readability.
3. On the Edit menu, click DWORD, type 6 for single processor servers or type 8 for multiprocessor servers, and then click OK.
4. Quit Registry Editor.

The default value for Dispatcher threads and RTS threads is 2. The default value for Kernel threads and Transfer threads is 3.

For more information, click the following article number to view the article in the Microsoft Knowledge Base: