XCON: The Mtadata Folder Is Not Referenced After You Upgrade from Exchange Server 5.5 to Exchange 2000 (272516)

IMPORTANT: This article contains information about modifying the registry. Before you modify the registry, make sure to back it up and make sure that you understand how to restore the registry if a problem occurs. For information about how to back up, restore, and edit the registry, click the following article number to view the article in the Microsoft Knowledge Base:

256986 Description of the Microsoft Windows Registry

SYMPTOMS

The Exchange 2000 Setup does not recognize the changes to the message transfer agent (MTA) database registry keys, and copies the Mtadata files into the default installation folder. This behavior occurs when you upgrade from Microsoft Exchange Server 5.5 to Exchange 2000, and when you reinstall Exchange 2000.

CAUSE

This behavior occurs if you edited the MTA database path and the MTA Run Directory registry entries or moved the Mtadata files with the Exchange Server 5.5 Performance Optimizer.

The system keeps working and no mail loss occurs, but your MTA databases will have some extra files that need to be cleaned up.

WORKAROUND

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.
After you run Exchange 2000 Setup:

Edit the MTA Run Directory registry entry so that it specifies the new Mtadata created under the default installation folder.
Locate the Mtadata folder that was created under the default installation folder, and delete all of the files that are not Db*.dat files.