The other day I was trying to removing the last Exchange 2003 Server from a customer and it would not let me uninstall the server with the error
“The component “Microsoft Exchange Messaging and Collaboration Services” cannot be assigned the action “Remove” because:
-One or more users currently use a mailbox store on this server. These users must be moved to a mailbox store on a different server or be mail disabled before uninstalling this server.”
The problem with this error message was, the server had all of its databases removed. so I know for a fact that it could not possibly have any mailboxes on it. Running a query in Active Directory Users and Computers (ADUC) for users with mailboxes on this server returned nothing.
For me I did a LDAP query in ADUC using Custom Search and Advanced on the same tab.
msExchHomeServerName=/o=Exchange Org/ou=First Administrative Group/cn=Configuration/cn=Servers/cn=EXCH2K3
This query returned a set of users who no longer had mailboxes but still had Exchange Attributes. I then “Right clicked” on the users and selected remove Exchange attributes. This cleared up the error message and the server was uninstalled in short order.Tweet