of course it shouldn't happen, but from time to time a tape goes bad.
Veeam doesn't help much with Identifying the bad tape - a tape job just fails and there are multiple possible errors all pointing to some bad tape. But since I've got up to 5 Tape drives per job, and the job might already have used a lot more than 5 tapes when the error happens, I don't see which tape in which drive is causing the problem.
When an error happens, output a message showing which tapes were in which drive at that time. Optimally the error message should identify which drive was responsible for causing the error: I suppose that there are multiple threads running, at least one for each tape drive. One of those threads reports a fatal error of any kind, just have it say "I was responsible for tape drive X, and at that time I was working on Tape Y"...
Thanks for your consideration.