attempt to write to or to erase [000000]GPT.SYS failed
Facility: EFI$CP, The OpenVMS EFI Partition Control Program
Explanation: GPT.SYS is present, but is apparently ill-formed or
ill-sized.
User Action: Use the DCL commands DIRECTORY and DUMP to determine
if the file is present, if the file is writable, and if storage
is allocated to all blocks of the file. In particular, use
DUMP/BLOCK=START=lastblock to dump the last allocated block of
the file. (If this dump of the last block fails, the GPT.SYS
file likely overhangs the end of the disk, and you cannot use GPT
bootstrap structures with this disk. You must either select and
use MBR-only operations or you must reinitialize the entire disk
with a valid GPT and reload the files.)