XADM: Downloading an NNTP Message with a Large Header May Cause the Information Store to Consume 100% of CPU Time

ID: Q197491

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
Version : WinNT:5.5
Platform : winnt
Issue type : kbbug