1. Select Start-> Run-> type cmd-> OK
2. When the diskpart, and press Enter
3. Type list volume to determine which drive will be hidden, select enter
4. Suppose that the selected drives have a drive D, then select volume 3, and press Enter
5. Type remove letter D, press Enter, and select Exit to exit the diskpart
6. The result can be checked in Windows Explorer, or can be restarted first.
7. To restore the drive to its original position, can perform steps 1-4, and then type assign letter D
source : beritanet
