DOCUMENT:Q197491 30-SEP-1999 [exchange] TITLE :XADM: Large NNTP Header Causes Store to Consume 100% of CPU Time PRODUCT :Microsoft Exchange PROD/VER:WinNT:5.5 OPER/SYS: KEYWORDS:exc55 EXC55SP3Fix ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Exchange Server, version 5.5 ------------------------------------------------------------------------------- SYMPTOMS ======== The Microsoft Exchange information store process (Store.exe) may consume 100 percent of the server's processor time. This is viewed by using the Windows NT Performance Monitor utility, clicking the Object:Process and the Counter:% CPU Utilization. Also, viewing the "% CPU Utilization" of all of the threads being used by the store process (in Performance Monitor, click Object:Thread and Instance:STORE; add all of the instance STORE to the chart) one thread will appear to be consuming 100 percent of the CPU time. CAUSE ===== An NNTP client was downloading a NNTP message from a folder in the Public Store, this message had a subject line greater than 20 KB. The buffer being used to hold the subject line was hardcoded at 20 KB. Therefore the code was continually looping trying to read in the contents of the subject line that were past this 20 KB limit. This process resulted in high CPU usage by the information store process. RESOLUTION ========== To resolve this problem, obtain the latest service pack for Exchange Server version 5.5. For additional information, please see the following article in the Microsoft Knowledge Base: Q191014 XGEN: How to Obtain the Latest Exchange Server 5.5 Service Pack The English version of this fix should have the following file attributes or later: Component: Information Store File Name Version --------------------- Gapi32.dll 5.5.2502 Mdbmsg.dll 5.5.2502 Store.exe 5.5.2502 STATUS ====== Microsoft has confirmed this to be a problem in Microsoft Exchange Server version 5.5. This problem was first corrected in Exchange Server 5.5 Service Pack 3. Additional query words: crash hang ====================================================================== Keywords : exc55 EXC55SP3Fix Technology : kbExchangeSearch kbExchange550 kbZNotKeyword2 Version : WinNT:5.5 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.