Click "Start" and then "Computer." Take note of the letter of the hard drive that you want to make bootable.
Click "Start" again, then type "CMD" into the search box. Press the "Enter" key. Wait for the Command Prompt window to appear.
Enter "bootsect /nt60 Z:" at the command prompt. Change the "Z:" variable to match the drive letter you noted in "Computer." Press the "Enter" key. Wait while Windows initializes the chosen hard drive and copies system files needed to make the drive bootable.