To clear everything on a hard drive by writing zeros 3 times on all bytes. Approx 1 hour per 350 gb, but probably a lot longer? (Note: you will never get anything back after this)
- Open cmd as administrator
-
Type: diskpart
-
Type: list disk
- Note the number of the disk you are trying to wipe clean
- Type: select disk [number]
- Double check the disk number because this is going to be irreversible
-
Type: clean all
To securely overwrite the free space on your hard drive (where old files can be recovered) and never be able to recover them:
- Open cmd as administrator. The following command cleans the c: drive
-
Type: cipher /w:c:
/W Removes data from available unused disk space on the entire
volume. If this option is chosen, all other options are ignored.
The directory specified can be anywhere in a local volume. If it
is a mount point or points to a directory in another volume, the
data on that volume will be removed.
End