This article was previously published under Q327167
This article has been archived. It is offered "as is" and will no longer be updated.
This article describes a fix that you can use to skip and remove user accounts when you upgrade Exchange Server version 5.5 to Exchange 2000 Server. In specific, it describes how to skip and remove user accounts that are not represented in the Active Directory directory service from the access control list (ACL) of mailboxes and public folders.
In an environment that is mixed (that contains Exchange Server 5.5 and Exchange 2000 Server) or an environment that was previously mixed, the ACL of mailboxes and public folders may contain user accounts that are not represented in Active Directory. Such users are "zombie" users.
Zombie users may cause a problem if the ACL from Exchange Server 5.5 is upgraded to match the NTDS format that is used in Exchange 2000 Server. Exchange 2000 Server tries to upgrade the ACL each time that the ACL has to be evaluated. If Exchange 2000 Server encounters a zombie user during the upgrade, the upgrade does not work. Exchange 2000 Server again tries to upgrade the ACL the next time that Exchange 2000 uses the ACL. Zombie users can lead to a range of issues, depending upon how prevalent they are in the environment.
Cumulative Patch Information
To resolve this problem, obtain the March 2003 Exchange 2000 Server Post-Service Pack 3 (SP3) Rollup. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:
813840 XGEN: March 2003 Exchange 2000 Server Post-Service Pack 3 Rollup
To resolve this problem, obtain the Microsoft Exchange 2000 Server Post-Service Pack 3 MDB patch. For additional information about how to do so, click the article number below to view the article in the Microsoft Knowledge Base:
329882 XGEN: Exchange 2000 Server Post-Service Pack 3 MDB Fixes Available
Microsoft has confirmed that this is a problem in Microsoft Exchange 2000 Server.