Restoring currupted exchange mailbox fro

One of my user malbox is corrupted and I need to restore the mailbox from tape.Since I have Exhange Agent from Arcserve, I tried restoring it base on instruction listed on CAI website. However, when I tried to expand the Private folder under Store Information, I cannot do so and I can’t see any of the mailboxes. I’ve chek the backup job and Brick level was selected and all mailboxes are suppose to be backup daily. Any ideas what isthe problem?