DOCUMENT:Q152945 19-DEC-1999 [exchange] TITLE :XCON: Microsoft Exchange Server MTA Not Responding PRODUCT :Microsoft Exchange PROD/VER:winnt:4.0,5.0,5.5 OPER/SYS: KEYWORDS:kbnetwork exc4 exc5 exc55 ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Exchange Server, versions 4.0, 5.0, 5.5 ------------------------------------------------------------------------------- SYMPTOMS ======== The Microsoft Exchange message transfer agent (MTA) service may terminate unexpectedly, causing message delivery to fail. When you view the Windows NT Application Event Log, it may show an entry similar to the following: Source: MSExchangeMTA Type: Error Category: Field Engineering EventID: 9405 Description: An unexpected error has occurred which may cause the MTA to terminate. Error: Exception c0000005 occurred at Address 20b1ec1. [BASE POP4 DOWN 4] (16) Viewing the Drwtsn32.log may show a failure of Emsmta.exe with an entry similar to the following: App: emsmta.DBG (pid=373) When: 8/5/1996 @ 9:18:54.343 Exception number: c0000005 (access violation) Viewing the thread that shows the FAULT will yield something like: State Dump for Thread Id 0x148 eax=00edd9cc ebx=000001a4 ecx=00000000 edx=00000001 esi=00edd9cc edi=022f002a eip=020b1ec1 esp=0189ff20 ebp=0189ff30 iopl=0 nv up ei pl nz na po nc cs=001b ss=0023 ds=0023 es=0023 fs=0038 gs=0000 efl=00000206 function: o4pgcb 020b1e94 668b4638 mov ax,[esi+0x38] 020b1e98 663d6500 cmp ax,0x65 020b1e9c 0f85b2000000 jne sgplthrd+0x54 (020b1f54) 020b1ea2 8b4645 mov eax,[esi+0x45] 020b1ea5 50 push eax 020b1ea6 e88d010000 call sgplimin+0xb8 (020b2038) 020b1eab 66833d089c1c0200 cmp word ptr [oivpmnod+0x9b8 (021c9c08)],0x0 020b1eb3 8b8366941c02 mov eax,[ebx+0x21c9466] ds:021c960a=00edd9cc 020b1eb9 7e0a jle sgpgsyst+0x31 (020b1ec5) 020b1ebb 8b0d049c1c02 mov ecx,[oivpmnod+0x9b4 (021c9c04)] FAULT ->020b1ec1 8901 mov [ecx],eax ds:00000000=???????? CAUSE ===== The MTA stops responding when two threads of the MTA attempt to release the same connection block structure, simultaneously. One thread has grabbed a system semaphore, and the other thread did not. The reason why this happens is still uncertain. It may correspond to a severe network problem between two stations (for instance, a complete router failure for a time, or a bridge problem). It is recommended that network problems be corrected (if they exist) as they appear to be the underlying cause of this failure event. STATUS ====== Microsoft has confirmed this to be a problem in Microsoft Exchange Server version 4.0. This problem was corrected in the latest Microsoft Exchange Service Pack. For information on obtaining the Service Pack, query on the following word in the Microsoft Knowledge Base (without the spaces): S E R V P A C K Additional query words: Access Violation GP Fault ====================================================================== Keywords : kbnetwork exc4 exc5 exc55 Technology : kbExchangeSearch kbExchange500 kbExchange550 kbExchange400 kbZNotKeyword2 Version : winnt:4.0,5.0,5.5 ============================================================================= 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 1999.