Backup Does Not Re-tension all Tapes of a Multiple Tape Backup Set

When you use your Windows 2000-based computer to perform a backup that uses multiple tapes, only the first tape of the multiple tape backup set is re-tensioned.

This problem occurs because individual tapes of a multiple tape backup set are not available for re-tensioning in the Windows 2000 Backup tool. Backup uses the Removable Storage Manager (RSM) to mount the first tape, and then issues a re-tension command to the tape device. If the tape backup catalog represents a multiple tape backup set, backup re-tensions the first tape but does not re-tension the remaining tapes of the backup set.

To re-tension tapes they must be associated with a standalone catalog and not a part of a multiple tape backup set. This can only be done by ejecting all the tapes that belong to the multiple tape backup set, and then deleting the backup catalog. After deleting the multiple tape catalog you can insert or inject the next tape of the backup set to permit it to be re-tensioned. This process can be repeated for all remaining tapes until all backup set tapes are re-tensioned.

To re-tension all tapes of a multiple tape set:

1. Use the RSM snap-in to eject all of the tapes associated with the multiple tape backup set.
   
   WARNING: It is critical that all tapes of the multiple tape backup set be ejected before you perform the following procedure or data could be lost. Verify that all of the tapes appear in the off-line library under RSM Physical Locations before proceeding. For additional information additional related information, click the article number below to view the article in the Microsoft Knowledge Base:
   244923  (http://support.microsoft.com/kb/244923/EN-US/ ) Deleting Backup Catalog May Erase Backup Set Member Tapes
2. Start Windows 2000 Backup (NTBackup.exe).
3. Click the Restore tab, right-click the catalog you want to re-tension, and then click Delete from System. This removes all the tapes in the off-line library for that backup set.
4. Manually insert (or use RSM to insert) the next tape you want to re-tension. This tape appears in the RSM Import media pool and should result in a message from Backup prompting you to allocate the media to backup. Click Allocate this media to Backup now to create a new catalog.
5. On the Restore tab, right-click the new catalog entry, and then click Re-tension.
6. After the re-tension is complete for that tape, repeat this procedure until all tapes are re-tensioned. After all tapes are re-tensioned, continue to the next step.
7. Eject and delete the catalog that represented the last tape you re-tensioned. Insert the first tape of the multiple tape backup set and click Allocate this media to Backup now. This creates a new catalog that can be used to restore data from the entire multiple tape backup set.

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.