If you manually rearrange media in a tape changer without using Removable Storage Manager (RSM) eject / inject wizards, RSM may attempt to mount the wrong media when an application calls for it. Since the media cannot be mounted, RSM (optionally) starts a full inventory for each piece of media in the changer. During this inventory, RSM re-catalogs media that was manually moved to different slots and moves it to the offline media library. For each piece of media that is re-cataloged in this way a new piece of media with the same name will appear in the import pool.

This issue can occur because RSM recognizes two pieces of media as exact duplicates.

To work around this issue, perform the following steps:

1. Leave all media that is in the offline pool in that pool.
2. Note the New media created and its location in the changer. This media is most likely in the Import pool. You can find its location in the changer if you right-click the media, and then click Properties.
3. Change the name of this media to something similar to "Bad Duplicate".
4. Use RSM to open the door and physically remove the media from the changer.
5. Close the door on the changer, and then take inventory.
6. After you complete the inventory, delete the new created media from the offline pool. This is the one you renamed in step 2.
7. Open the door again, and place the media into any available slots in the changer.
8. Take inventory again. The media is compared with the off-line records and brought online.

This behavior is by design. Duplicate media is always treated like different media and will appear in the import pool during a full inventory.

To illustrate this behavior, lets use the following example: For additional information about how RSM identifies media, click the article number below to view the article in the Microsoft Knowledge Base:

The administrator (or operator) gains door access to the changer and moves 'Backup Tape 1 -1' to slot 4 and 'Backup Tape 4 -4' to slot 1. After closing the door to the changer, the operator now opens Ntbackup.exe and attempts to catalog 'Backup Tape 1 -1'. RSM cannot mount the tape in slot 1 because it is not the tape that is cataloged.

When the mount does not complete, RSM performs a full inventory and the following events occur:

1. RSM identifies the media in Slot 1 and finds a different tape. It moves the tape that was in that location (Backup Tape 1 -1) to the off-line media pool and creates new records in the RSM database for the tape it found in that slot.
2. Because it did not find the tape in slot 1 (Backup Tape 4 -4) in the off-line library it treats the OMID it found on the tape as a duplicate of an OMID on a tape in a different slot (the one it thinks is in slot 4).
3. RSM identifies tapes in slot 2 and slot 3 and they match what is recorded in the RSM database so no changes are necessary.
4. When it inventories the tape in slot 4, it finds a tape it did not expect but finds this tape in the off-line library (Backup Tape 1 -1) so it marks it online again in the new slot.
5. The tape that used to occupy this slot (Backup Tape 4 -4) is put in the off-line location.

Now RSM has duplicate records for the tape that was in slot 4 (Backup Tape 4 -4), one off-line and one on-line. When RSM was identifying the media in slot 1 (step #1 above) it created new records in the RSM database for this media, which resulted in a new LMID, PMID, and PartID. Windows NT Backup refers to this media using the LMID so when the program attempts to mount the tape (Backup Tape 4 -4) it refers to the LMID that points to the tape in the off-line library. RSM notifies the operator to mount this tape even though it is in the library.