Recover expired backup set from tape

I am trying to restore a mailbox from a saved mailbox database.  The backup set is on tape and shows as expired, therefore it does not show up when selecting from the backup sets, and it is within the date range.  The backup set was duplicated to tape for long term storage.  I tried duplicating the backup set back to disk and changed the expiry date and ran a catalog over it.  It still does not show.  What am I missing?  Can the expiration date of the backup set on tape be changed? 

Thanks to all