To restore individual public folder messages from tape, you must first duplicate the backup sets that contain the messages to a backup-to-disk folder. You can then restore the data from that folder.
The backup that you want to restore from must be a full backup or a copy backup. If there is an incremental backup that is subsequent to the full backup, then you can restore individual items from the incremental backup. The backup sets for the full backup and the incremental backup must be on the same volume.
You cannot restore individual public folder messages from tape if the original backup is an incremental backup.
To restore individual Exchange public folder messages from tape by duplicating backup sets to disk
Insert the tape containing the required Exchange backup sets into a tape drive.
On the menu bar, click File, and then click New > Duplicate Backup Sets Job.
On the Properties pane, under Destination, click Device and Media.
After the job completes, run a restore job to restore the individual public folder messages from the Exchange backup sets that are duplicated in the backup-to-disk folder.
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