DOCUMENT:Q247782 11-JUN-2002 [exchange] TITLE :XCON: Mail Slow Across Connectors, with Event IDs 3120 and 9316 PRODUCT :Microsoft Exchange PROD/VER:winnt:5.5 OPER/SYS: KEYWORDS: ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Exchange Server, version 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 ======== When you administer Microsoft Exchange Server 5.5, you may notice that mail transfer across connectors is extremely slow. Event Viewer may record the following events in the application log: Event ID: 3120 Source: MSExchangeMTA Type: Warning Description: A resource limit has been reached when attempting to open an association. Number of sessions configured: 30 Event ID: 9316 Source: MSExchangeMTA Type: Warning Description: An RPC communications error occurred. No data was sent over the RPC connection. Locality table (LTAB) index: x. Windows NT error: 9317. CAUSE ===== This behavior can occur when the Message Transfer Agent (MTA) experiences a resource shortage. RESOLUTION ========== 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 resolve this behavior, change the 'Concurrent XAPI sessions' value in the registry: 1. Start Registry Editor (Regedt32.exe). 2. Locate the following key in the registry: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeMTA\Parameters\ 3. Double-click the Concurrent XAPI Sessions value. 4. In the Radix area click Hex, in the Data box type "50" (without the quotation marks), and then click OK. NOTE: By default this value is set to 50 hex (80 decimal). If Performance Optimizer is run with default settings selected, the value will be set to 30. 5. Quit Registry Editor. Additional query words: ====================================================================== Keywords : Technology : kbExchangeSearch kbExchange550 kbZNotKeyword2 Version : winnt: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.