Microsoft KB Archive/241228

-

The information in this article applies to:


 * Microsoft Windows NT Server version 4.0
 * Microsoft Exchange Server, versions 5.5, 5.5 SP1, 5.5 SP2, 5.5 SP3

-

SYMPTOMS
Your server may become slow or unresponsive. The server may also become slow over time as more users log on and open their mail boxes. This may seem to indicate a memory leak, but it is not the case in this instance.

CAUSE
This behavior can occur if Trend Micro Scan Mail for Exchange Server is running on an Exchange server with more than 1,000 mail boxes. Trend Micro has tested their product and has approved it for 1,000 mail boxes or less.

RESOLUTION
To resolve this issue, disable the Real-Time Scanning option in Scan Mail, or completely uninstall Scan Mail.

MORE INFORMATION
Scan Mail runs a process called Real Scan. This process scans the Exchange store and causes very high memory usage. According to Trend Micro, Scan Mail must start a separate instance of Real Scan for every 247 mail boxes. On a large-scale Exchange server, this starts many instances of Real Scan and causes performance degradation. You can observe this by analyzing a Performance Monitor log from the server. The Store process may appear to be leaking memory; there is a steady increase in the "private bytes" usage for the process. However, you may also see separate instances of the Real Scan process running. Real Scan seems to function normally, but it is scanning the Exchange store and causing high memory usage.

For additional information, click the article numbers below to view the articles in the Microsoft Knowledge Base:

"Q175658 Gathering Information for Troubleshooting Performance Issues" "Q150934 How to Create a Performance Monitor Log for NT Troubleshooting"

The third-party products discussed here are manufactured by vendors independent of Microsoft; we make no warranty, implied or otherwise, regarding these products' performance or reliability.

Additional query words:

Keywords : kb3rdparty kbenv

Version : winnt:4.0,5.5,5.5 SP1,5.5 SP2,5.5 SP3

Platform : winnt

Issue type : kbprb