Restore failed: storage volume is inaccessible

Hi all,
tried to restore a file from tape but endup with error saying that "storage volume is inaccessible"

dsmc restore /TM/planfiles/plan.20120311.131713 /tmp/testrestore/

ANS4035W File '/TM/planfiles/plan.20120311.131713' currently unavailable on server.

** Interrupted **
ANS1114I Waiting for mount of offline media.

on TSM server's actlog

Code:

>q actlog search=restore



Date/Time                Message

--------------------     ----------------------------------------------------------

10/02/12   16:05:38      ANR0565W Retrieve or restore failed for session 72355 for

                          node LNX8 (Linux86). The storage volume

                          C00636 is inaccessible. (SESSION: 72355)

and

Code:

>q volume C00636 f=d



                   Volume Name: C00636

             Storage Pool Name: BKUP

             Device Class Name: 3592H-C

            Estimated Capacity: 1.0 T

       Scaled Capacity Applied: 100

                      Pct Util: 93.1

                 Volume Status: Full

                        Access: Unavailable

        Pct. Reclaimable Space: 7.0

               Scratch Volume?: Yes

               In Error State?: No

      Number of Writable Sides: 1

       Number of Times Mounted: 5,991

             Write Pass Number: 1

     Approx. Date Last Written: 03/23/12   16:25:36

        Approx. Date Last Read: 01/20/12   23:03:33

           Date Became Pending:

        Number of Write Errors: 0

         Number of Read Errors: 0

               Volume Location:

Volume is MVS Lanfree Capable : No

Last Update by (administrator):

         Last Update Date/Time: 01/20/12   23:03:23

          Begin Reclaim Period:

            End Reclaim Period:

  Drive Encryption Key Manager: None

How to troubleshoot this ?

Thanks in advance!