I don't know very much about Exchange (which will probably be obvious when you read the rest of this), but I am stuck dealing with this situation.
The store is full. We are going to implement an archiving solution, but we need room now. There is an old user that I want to remove to give us some breathing room, but the Email is accessed by another user at times.
My thoughts - backup user to PST (I only know how to do this via Outlook - is there a better way?) then remove mailbox. Offline defrag to get space back. Set that one user up for access to the PST file. When the archiving is setup and there is room again, create the mailbox and import the PST file.
Does this make sense? Is there a better way?