Hello,
What you are basically trying to tell us here is that: When you launch the backup job you physically and logically remove the old tape to 'used' media set and the 'daily' media set contains just one tape logically and the tape drive also contains the same tape physically.
After the job completes 0.1% of the times the media set 'daily' shows two tapes one black and the pther blue.
What we recommend is inventory and catalog the two tapes that you see in backup exec. next check which of these corresponds to the tape that is physically inserted in the tape drive.
Next find the physical tape that the other tape in Bcakup exec corresponds to.catalog and inventory this tape and update us on its contents.
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