Backup Exec 2012 SP4

 Hi,

        I am using backup exec 2012 SP4 which is installed on windows server 2008 R2. And i am backup Data server and SQL databases, Backup was working fine but since two weeks it is not backing  up to my deduplicaiton storage drive.It give an Final Error : 0*2000040d-S_TF_NO_TAPE_PRESENT.So, can anybody can help me to find the solution.

Thank You