Clean
DiskPart
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Syntax: clean [all]
Removes any and all partition or volume formatting from the disk
with focus. On master boot record (MBR) disks, only the MBR
partitioning information and hidden sector information are
overwritten. On GUID partition table (GPT) disks, the GPT
partitioning information, including the Protective MBR, is
overwritten; there is no hidden sector information.
all
Specifies that each and every sector on the disk is zeroed, which
completely deletes all data contained on the disk.
For an example of using the clean command, click here