Hello; My Administrator mailbox says it is a legacy Mailbox in my Exchange 2010. When I try to move it it claims to be attempting to run the command on a server that was decommissioned years ago. How do I fix this? Thank you, David Kellett

What do you use this "administrator" mailbox for? There is no such thing in the 2003/2007/2010 Exchange world, so it was created maybe in Exchange 5.5 as the system account or as the postmaster account or to serve as an Exchange administrator generic account? Either way, if you dont really need it, you can simply mail-disable it.

There is no "administrator" mailbox per se as Andy mentioned, if it's a service account mailbox, try running the set-mailbox administrator -applymandatoryproperties then try to move the mailbox. If it fails post the error.James Chong MCITP | EA | EMA; MCSE | M+, S+ Security+, Project+, ITIL msexchangetips.blogspot.com

This worked. It is gone. Thank you. It is strange, however, since I've never had an Exchange 5.5 Server. Thank you, David Kellett