This is to remove all partitions on a hard drive including the pesky recovery partitions on USB backup hard drives.
Open command prompt and type the following lines hitting enter after each step:
2. list disk
3. look for the disk you want (most likely Disk 1 because Disk 0 should be boot disk)
4. select Disk 1 (if it is in fact Disk 1 that you want to mess with)
After those steps the drive will have all partitions erased and the drive its self will have to be initialized then partitioned for use.
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