1, the test is in a computer has two hard drives, operating system of the disk does not move, just clear another hard disk of the EFI partition. Start → run → input: Diskpart Click OK to open cmd.
2, then, Input: List disk Press ENTER (enter key) → Select the disks that need to be modified.
3, here is a disk 0, and then enter: Select Disk 0 back to the car to select 0.
4, Re-enter: Clean press ENTER (enter key) can erase all the messages on the disk.
5, and then repartition (right click on the unpartitioned disk), using the wizard to the disk space to operate (format), you can use the disk.