Hello,   Yes, mark valid is your best bet at this point.  You can create a snapshot first if you wish.  Then you can revert quickly w/o needing 2x the space.   You need to rescan or even reboot the hosts afterwards.   Regards,  Don 
HiI have a Equallogic PS6000 running FW V5.2.6 with 4400 Lost Blocks after a power outage. Other places in this support forum I see a script that can be run on the device. Since the devices are are of support where can I obtain the script?Kind regards Christian
Equallogic PS6000 Lost Block after power outage