Netbackup 7.6 - Cannot delete from diskpool

Hi,

I need to delete some image on a diskpool (who will be deleted after) so i list image contains with this command :

bpimmedia -L -stype DiskPool -dp "mydispoolname"

From here i have a complete list of image on this pool (example below) :

Backup-ID          Policy                 On Hold Indexing    ScheduleType
Copy  Frag  Expires                   DiskType             DiskPoolName              DiskVolume                StorageServerName    On Hold
-------------------------------------------------------------------------------------------------------------------------------------------
mutdag001.hebergemen CFI-EXCH-MBX         0       0           FULL
1     1     1432918241                DiskPool             DCRCVXNAS003POL002        O:\                       dcrcvxsrpbck003.shd. 0      
1     2     1432918241                DiskPool             DCRCVXNAS003POL002        O:\                       dcrcvxsrpbck003.shd. 0      
1     3     1432918241                DiskPool             DCRCVXNAS003POL002        O:\                       dcrcvxsrpbck003.shd. 0      
1     4     1432918241                DiskPool             DCRCVXNAS003POL002        O:\                       dcrcvxsrpbck003.shd. 0     

But when i try to delete those image (command below), the command returns this :

bpexpdate -M dcrsrvbck001 -notimmediate -force -d 0 -copy 1 -backupid ‘mutdag001.hebergemen’

an invalid entry was encountered

I tried with the full backupid (whos my client name) same result.

Any help would be appreciate.