A system and method for operating a storage library. The system comprises a management server, a media agent connected to the management server, a library connected to the media agent and a database connected to the management server. The management server controls the media agent to monitor for the addition or removal of a piece of media in the library. When the media agent determines that the piece of media has been added to the library or removed from the library, the media agent causes the library to read a media label stored as data on the piece of media, the media label including an identifier identifying the piece of media. When a backup or restore is performed, the system checks the media label to ensure that the correct media is being used. Inventory procedures are disclosed. Media labels are stored in a database along with an indication of the corresponding slot where the media is stored, a time when the label was put on the medium, and a confidence parameter indicating how confident the system is that the particular medium is stored in the respective slot.