Exchange 2007 Restore Mailbox Data Deleting

Hello,

Summary: Trying to restore an old Exchange 2007 Mailbox, the restore seems to work as I see data in Outlook however as soon as the restore is complete the data gets deleted.
Details: We have Exchange 2010 with all users moved over. One user was missing some very old mail from our Exchange 2007 server. I powered on the Exchange 2007 server, recreated the DB the users mail was in as it was no longer there and created a Restore User in a different existing DB on it. Via Arcserve I restored the DB into a Recovery Group, mounted it and selected the user's mailbox to restore to the Restore user /restore folder. The restore starts OK and runs for 6+ hours (huge mailbox). I can open Outlook of the Restore user and view the mail in the /Restore folder and was able to copy some to a .PST archive. When the restore completes, the data starts deleting itself and within a few seconds GBs worth or recovered data is gone. I've tried two different tapes from different times with the same results.
Any help would be greatly appreciated.