On the Cache-A with the tape inserted, open terminal.

>> Navigate to the share

cd /media/vtape/

>> Make recovery directory

mkdir recovery

chmod -R 777 recovery/

>> Stop tape manager

/etc/init.d/tapemgr stop

>> rewind the tape

mt -f /dev/nst0 rewind

(quick note, there is a timeout period for tape commands.  That means that there might still be part of tapemanger running.  If you get an error saying the device is busy, wait 5-20 min and try again)

>> Start recovery:

while [ 1 ]; do tar xvf /dev/nst0 -b 300 -C /media/vtape/recovery/; done

(this program will run continuously, it does not know when to end.  Between each archive there is a blank space that the machine will report as: This does not look like a tar archive.  It will then proceed to the next session, hit the empty space, and repeat.  You will know when the whole process is done when it gives the "this does not look like a tar archive"" over and over again.  When you get to this point, ctrl+c will stop the recovery
>> rewind tape, start tape manager back

(same note applies here as well, if you get an error saying the device is busy)

mt -f /dev/nst0 rewind

/etc/init.d/tapemgr start

>> At this point the UI will probably tell you again that the tape is damaged.  I would doubles check the 'recovery' folder on the share and make sure that the files are all there.  Then proceed with erasing the tape.