XFOR: MCIS 2.0 Caches Mailbox Index Files (208217)

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256986 Description of the Microsoft Windows Registry

SUMMARY

Microsoft Commercial Internet Server (MCIS) version 2.0 caches mailbox index (.idx) files by default. Administrators may find themselves unable to immediately remove users' mailboxes without first having to shut down the mail services or the Microsoft Internet Information Server (IIS) administrator service. This apparent inability to remove the mailbox is rooted in the fact that the file handle associated with the mailbox index file is open and cached.

MORE INFORMATION

This behavior is by design. MCIS will cache the index file handles by default. It will only close the cached file handle when the following two conditions are true:

The cache is 90 percent or more occupied.

-and-
The cached file has been idle for 10 minutes. If the cache is less than 90 percent occupied, the 10 minute time-to-live (TTL) is ignored.

Administrators can control the cache behavior using the registry. Adjustments can be made to the following key:

WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

HKLM\System\CurrentControlSet\Services\SMTPSVC\Parameters\CachedHandle

The following values are not present by default but can be added.

CacheEnable

REG_DWORD
Default value: 1
Setting CacheEnable to 0 disables caching.

CacheEntryNum

REG_DWORD
Default value: 1024
CacheEntryNum sets the size of the cache.

CacheTTL

REG_DWORD
Default value: 10 (minutes)
CacheTTL sets the time-to-live.