A. The two switches you're looking for are /nopoll and /missingtape. The /nopoll switch is great for erasing troublesome tapes. The syntax

ntbackup /nopoll

tells NT Backup to erase the tape. Don't use /nopoll with other parameters.

The /missingtape switch tells NT Backup that a tape is missing from a backup set that spans several tapes. Thus, it should treat each tape in the set as a single unit. Use the syntax

ntbackup /missingtape