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:
1. diskpart
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)
5. clean
After those steps the drive will have all partitions erased and the drive its self will have to be initialized then partitioned for use.
Keywords:
hard, drive, HDD, Partition, USB, backup, diskpart