What do you mean by "Not work the automatic dismount barcodes"?

Is it not unmounting? Can you specify more clearly?

Normally when the operation of writing-reading in a tape finishes, automatically it realises the dismount of the tape it eject and it, but at the moment it realises no longer it automatically.

I agree with Peter. Since you reconfigured the library you probably loaded default setting scheme which assume tapes are not to be unloaded after done with read or write operation. Check timers tab and look for device idle timeout value there - most probably it is set to 0 - change to 1 or whatever value in minutes you want.

Indeed Peter, is the " Timers Tab " , on the " idle device timeout" Set value to " 1" and is OK. Thanks you very much

Indeed Peter, is the " Timers Tab " , on the " idle device timeout" Set value to " 1" and is OK. Thanks you very much