DOCUMENT:Q257995 11-JUN-2002 [exchange] TITLE :XCON: Dynamic RAS Connector Server Does Not Work with 9315, 9405 PRODUCT :Microsoft Exchange PROD/VER:winnt:4.0,5.0,5.5 OPER/SYS: KEYWORDS:exc4 exc5 exc55 ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Exchange Server, versions 4.0, 5.0, 5.5 ------------------------------------------------------------------------------- IMPORTANT: This article contains information about modifying the registry. Before you modify the registry, make sure to back it up and make sure that you understand how to restore the registry if a problem occurs. For information about how to back up, restore, and edit the registry, click the following article number to view the article in the Microsoft Knowledge Base: Q256986 Description of the Microsoft Windows Registry SYMPTOMS ======== The message transfer agent (MTA) service may stop responding on an Exchange Server computer that one or more Dynamic Remote Access Service (RAS) Connectors is installed on. The following events may be logged in the application event log: 9315 MTA A resource limit has been reached when attempting to open a RAS association. The number of entries configured is 2. 9405 MTA An unexpected error has occurred which may cause the MTA to terminate. Error: Double acquire of semaphore 2210. CAUSE ===== This problem can occur because, for a number of possible reasons, you need to increase certain MTA RAS registry parameters. You may need to increase these registry parameters if a high number of Dynamic RAS Connectors are installed on the Exchange Server computer, or if you run Performance Optimizer with certain settings or through manual intervention. RESOLUTION ========== The default value for the RAS LAN-MTA DMOD Threads value is 2. The default value for the "Concurrent connections to RAS LAN-MTAs" value is 0xa (10 decimal). To resolve this problem, note these registry values and, if necessary, increase them to the values provided in the following steps: 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. 1. Start Registry Editor (Regedt32.exe). 2. Locate the RAS LAN-MTA DMOD Threads value under the following key in the registry: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeMTA\Parameters 3. If necessary, increase this value from 2 to 4; on the Edit menu, click String, type "4" (without the quotation marks), and then click OK. 4. Locate the "Concurrent connections to RAS LAN-MTAs" value under the following key in the registry: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeMTA\Parameters 5. If necessary, increase this value from 2 to 10 (decimal); on the Edit menu, click String, type "10" (without the quotation marks) (decimal), and then click OK. 6. Quit Registry Editor. 7. Restart the MTA service after you make these changes so that they take effect. WORKAROUND ========== To work around this problem, restart the MTA service. Even if you do not make the registry changes in the "Resolution" section of this article, if you restart the MTA service you alleviate this problem temporarily. If you want a more permanent solution, make the registry changes in the "Resolution" section of this article. Additional query words: error Q253310 ====================================================================== Keywords : exc4 exc5 exc55 Technology : kbExchangeSearch kbExchange500 kbExchange550 kbExchange400 kbZNotKeyword2 Version : winnt:4.0,5.0,5.5 Issue type : kbprb ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 2002.