DOCUMENT:Q178204 20-MAR-1999 [exchange] TITLE :XCON: MTA Using 100% CPU on Receiving Message PRODUCT :Microsoft Exchange PROD/VER:WINDOWS:5.0 OPER/SYS: KEYWORDS: ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Exchange Server, version 5.0 ------------------------------------------------------------------------------- SYMPTOMS ======== Performance Monitor shows a constant 100 percent CPU utilization caused by the message transfer agent (MTA). The computer running Microsoft Exchange Server still responds to user input, but does so slowly. The service MSExchangeMTA cannot be stopped using either Control-Panel Services or the "Net Stop" command. CAUSE ===== The MTA may cause 100 percent CPU usage when receiving a specific message. The message must originate from Microsoft Mail and be sent via its X.400 Gateway. It can either be sent directly to the Exchange Server MTA or routed through an intermediate third-party X.400 system, such as MAIL.X, to Exchange Server. Additionally, the message has to contain an attachment. On processing the attachment, the MTA enters an infinite loop, thus causing 100 percent CPU usage. RESOLUTION ========== To resolve this problem, obtain the fix described below or wait for the next Microsoft Exchange Server 5.0 service pack. The fix installs the following files in the following folders: File Location(s) -------------------------- Address.dll Exchsrvr\Bin (See note below) Dbserver.sch Exchsrvr\Mtadata Dcprods.cat Exchsrvr\Bin Exchsrvr\Mtadata Ems_rid.dll Exchsrvr\Bin Emsmta.exe Exchsrvr\Bin Infotlog.cfg Exchsrvr\Mtadata Infoxlog.cfg Exchsrvr\Mtadata Mapi32.dll Winnt\System32 Mmiext.dll Exchsrvr\Bin (See note below) Mtacheck.exe Exchsrvr\Bin Mtamsg.dll Exchsrvr\Res P2.xv2 Exchsrvr\Bin Exchsrvr\Mtadata P3.tpl Exchsrvr\Mtadata P772.tpl Exchsrvr\Mtadata X400om.dll Exchsrvr\Bin X400omv1.dll Exchsrvr\Bin (See note below) Notes ----- - If the Microsoft Mail Connector is installed on the server, you should manually copy the Address.dll and X400omv1.dll files to the Exchsrvr\Connect\Msmcon\Bin folder after applying the fix. - If the Internet Mail Service is installed on the server, you should manually copy the Address.dll and X400omv1.dll files to the Exchsrvr\Connect\Msexcimc\Bin folder after applying the fix. - If the Admin.exe utility is installed in a folder on the server other than the Exchsrvr\Bin folder, you should manually copy the Mmiext.dll file to the folder in which Admin.exe is installed after applying the fix. STATUS ====== Microsoft has confirmed this to be a problem in Microsoft Exchange Server version 5.0. This problem has been corrected in the latest U.S. Service Pack for Microsoft Exchange Server version 5.0. 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 MORE INFORMATION ================ The problem described in this article was introduced with an Exchange Server 5.0 post SP1 hotfix. Only MTA versions with build numbers 1459.17 and higher will show the above-described behavior. ====================================================================== Keywords : Technology : kbExchangeSearch kbExchange500 kbZNotKeyword2 Version : WINDOWS:5.0 Issue type : kbbug Solution Type : kbfix ============================================================================= 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.