Article ID: 327772 - View products that this article applies to.
This article was previously published under Q327772
After you install Exchange 2000 Server Service Pack 3 (SP3) or later, the information store database does not mount.
This issue may occur when you upgrade any pre-SP3 version of Exchange 2000 Server to Exchange 2000 Server SP3 or to any later version. For example, if you try to upgrade Exchange 2000 SP2 to Microsoft Exchange Server 2003, you may experience this issue.
You may find events similar to the following in the application log of Event Viewer:
Event Type: Error
Event Type: Error
Note In Event ID: 505 (Description Section), drive refers to the drive on which the Exchange information store database is installed.
This issue may occur when you apply Exchange 2000 Server Service Pack 3 to an Exchange 2000 server that contains an information store database that is compressed by using NTFS file system compression. This issue may also occur when you upgrade an Exchange 2000 Server computer to Exchange Server 2003. Exchange 2000 Server Service Pack 3 and Exchange 2003 prevent compressed information store databases from mounting.
Files that are managed by extensible storage engine (ESENT or ESE) are not designed to be stored on a compressed drive. The extensible storage engine depends on sector independence for log-based recovery, and compression of files invalidates sector independence. Compression should not be turned on for volumes hosting ESE databases, or any database that uses write-ahead logging.
Before Exchange 2000 Server Service Pack 3, compressed information store databases were allowed to mount. However, corruption can result in any Exchange 2000 information store databases or information store logs that have been compressed by using NTFS compression.
With Exchange 2000 Server Service Pack 3 and later, compressed information store database files of 128 megabytes (MB) or fewer are automatically decompressed. When database files grow to larger than 128 MB, the database does not mount and the error messages are generated in the Application Log. Exchange 2000 Server Service Pack 3 and Exchange Server 2003 prevent compressed databases larger than 128 MB from mounting.
Because the public information store database may be smaller than 128 MB, it may mount. However, apply all the steps in the "Resolution" section of this article to all Exchange 2000 Server or Exchange Server 2003 information store databases that are in a compressed folder, regardless of whether they can be mounted or not.
For additional information about corruption of Exchange information store databases because of NTFS compression in earlier versions of Exchange, click the following article number to view the article in the Microsoft Knowledge Base:
(http://support.microsoft.com/kb/170009/ )NTFS compressed volume causes store to fail
To resolve this issue, you must decompress the folders where the information store databases and logs reside, defragment the databases, and then perform an online Exchange-aware backup of the Information Store storage groups where the databases and logs reside. To do this, follow these steps.
Dismount the databases
Note Perform this procedure only if the databases are still mounted.
Decompress the folder where the databases and logs reside
Perform offline defragmentation of databasesAn offline defragmentation of the databases generates a new database table. The old database table may have become unstable because of compression.
Note 110 percent of the database file size is required as free space on the drive before the database file can be defragmented.
For additional information, click the following article number to view the article in the Microsoft Knowledge Base:
(http://support.microsoft.com/kb/183888/ )Free disk space requirements for Eseutil.exe
(http://support.microsoft.com/kb/192185/ )How to defragment with the Eseutil utility (Eseutil.exe)
Remount the databases
Perform an immediate, online Exchange-aware backup of the storage groups where the databases and logs resideFor additional information about how to perform an online Exchange-aware backup of Exchange 2000, click the following article number to view the article in the Microsoft Knowledge Base:
(http://support.microsoft.com/kb/258243/ )How to back up and restore an Exchange computer by using the Windows backup program
For additional information about Jet databases and compressed drives, click the following article number to view the article in the Microsoft Knowledge Base:
(http://support.microsoft.com/kb/318116/ )Issues with Jet databases on compressed drives
Article ID: 327772 - Last Review: December 3, 2007 - Revision: 4.4