When I had a similar error we finally traced it to incorrectly defined
drives. Tivoli will accept some definitions even if they are incorrect.
Make sure the elements are not transposed.  If your defining SCSI drives,
make sure that the drives and rmts are not transposed.  If it's a SCSI card,
make sure it's a supported SCSI card. 4B cards don't supported with LTO
drives.  


Doug Ruska
904-791-8099