Other than a bad tape or drive, is there anything else that would cause "Mount Failed - User canceled a Physical Volume Library operation" errors?
I administer multiple locations, each of which have the identical hardware configuration (same servers, same tape drives, same media), and I'm plagued by Mount Failed errors at least 2-3 times a week at every site. There doesn't seem to be anything consistent about the errors, either. The tapes are being swapped in a weekly rotation at each site and the errors do not always occur on the same day each week.
At this point, I've tried new tapes and have swapped one of the tape drives (with the identical model), but this does not fix the problem. Any help would be much appreciated.