Hi,
In order to stop the job, make sure that there are no alerts pending for the same. If there are no alerts then try stopping and restarting the services. Try rebooting the server if the above fail.
Please perform a repair database. Open BEUTILITY.EXE from \program files\veritas\backup exec\NT.
Select All media server by right clicking, add the media server and select repair database from the task pane on the left.
We hope this will help.