"clean" zeroes the sectors in the first and last MiB of the disk. If you aren't careful you can "clean" the wrong disk. I tried this with a UEFI Win10 system. A HD0 "clean". After "clean" there was no Protective MBR, no Primary or Secondary GUID partition tables. Win10 didn't boot. A complete fix is possible. Briefly... Undelete the partitions Create a GPT disk Edit the "Type" of the ESP and Recovery partitions Do a BCD Edit on the ESP Win10 now boots.
