The attempted operation cannot be completed on the specified library. Either there are no available drives with the specified format, or the volume has the wrong access mode. A drive can be unavailable because another application opened the drive. This message can also be issued if a CHECKIN or LABEL command is issued and no drive is available to service the operation. This can occur when all drives are mounted by other processes or sessions, or the device type was incorrectly specified.
The attempted operation ends.
Use the QUERY DRIVE command to check the online status of the drives. Drives that are marked "Unavailable since hh:mm yy/mm/dd" are drives taken offline by the server at the time specified because of hardware failures or the inability to open the drive. Use the QUERY MOUNT command to query mounted drives and their mount mode. If there are mounted volumes with an IDLE status, use the DISMOUNT VOLUME command to free the drive, and retry the original operation.