Regarding License information about Stand-alone drive and Libraries, please refer the following information.
Backup Exec media server will connect an unlimited number of individual "stand alone" backup drives, physical or virtual, optical, or one single backup drive within one physical or virtual autoloader, library, robotic library or robotic media changer. Those devices with two or more drives require a separate Library Expansion Option license for each additional drive beyond the first drive.
Please let us know if you have ( LEO ) license for the additional drive that you would like to use with Backup Exec. If you do not have LEO license then you will have to contact our Sales department and obtain the same in order to use the additional drive that you want to use.
Here we would like to add that, tape drives or robotic libraries must always be connected locally to the Media( Backup Exec ) server. Any tape drive or robotic library that is remotely connected to any remote machine cannot be controlled or operated from Backup Exec server.
Title:- Event ID 58053: "!" is reported when starting Backup Exec http://seer.support.veritas.com/docs/252407.htm
We hope this helps.