Hi all, I have recently transitioned from Exchange 2003 to 2010 in co-existence phase. I'm not at the stage where Exchange 2003 can be decommissioned. All Mailboxes have been moved, Public Folders replicated and moved. OAB etc done. I have changed the RUS server in the Exchange 2003 console. I now plan to shutdown the Exchange server for 2 weeks to ensure there is nothng I have missed. Will shutting the server down cause any issues, with 2010. Will it try to contact it with the routing group that was setup automatically during setup? Is this the best method or would you just run-install. When I do come to un-install do I need to delete the mailstores and routing groups first? Thanks for your help Chris

There must be something triggering that message still on the system. In a few rare instances I have seen it happen when the system mailboxes are not set correctly - usually where there has been multiple databases and the database that holds the system mailbox wasn't the last database removed. Try this - recreate the mailbox database on the server and then restart the information store and system attendant services. That forces the system mailboxes to recreate. Then drop the mailbox database again. Finally attempt the removal of the server again. Simon. Simon Butler, Exchange MVP Blog | Exchange Resources | In the UK? Hire Me.