Here's our situation. A user at another location was somehow deleted from AD. The local admin re-created the user's account, but was never able to recover any of the mail. I restored the entire MDB from backup and mounted as an RDB (recovery database) on Exchange. The problem I have now is two-fold.
One, when I run the command to recover the items from the RDB, I'm getting the error "Database "RDB" is not a recovery database."
That would be ok if my second option would work: New-MailboxExportRequest
However, THAT also fails, with the error "A positional parameter cannot be found that accepts argument 'userid'
I've tried using the display name, email ID, user ID. Nothing works. If I can simply export to PST and send the guy that file, we'd be fine.