You don't say how you replaced tape in the clot (using what method) and that could be related...

Try a library reset and perform a full Inventory, this should bring back the volume label put your device in Ready mode again.

Hi,

I made a reset of the library and dit the complete inventory of tapes. I also did a reset of the backup server, but unfortunately did not take much effect. Device \\.\Tape0 is still in the service mode. So i am not able to change it. Scheduled jobs are running a lot slower because only one Tape device is working.

Best regards
Milan

Device what get out from service mode automatically - you must do it on your own through device management in NW GUI.

If i read it correctly, you may have used the jukebox to perform the tape movement, this will definately throw the networker server out of sync, only use networker to do media movement

After placing the Device back to ready, clean the drives and clean them often, check for other errors on FC or SCSI bus, bad tape or drive order mismatch if it happnes again.
HTH

Thanks for helping, it worked out fine.

regards,
M*