When you delete media from Backup Exec, all records of the media are removed from the Backup Exec Database. These records include catalog information, media statistics, and other information that is associated with the media. You can only delete media when it belongs to the Retired Media set.
Media can only be deleted from Backup Exec after it has been associated with the Retired Media set.
When deleted media is reused in Backup Exec, it is recognized as imported media. Before you can restore from the media, you must catalog it.