How to Erase a Hard Drive on Command Prompt
The command prompt is a text-line utility that you can use on a Windows computer to perform many of the same types of operations that are available through normal, graphical user interface driven facades. For example, instead of using the Disk Management utility to erase a hard drive, you can erase the hard drive through the command line utility with just a few lines of commands.
Open the "Start" menu and click on the "Run..." label.
Type "cmd" into the Run window and press the "Enter" key.
Type "format x: /fs:ntfs" into the command prompt window, replacing "x:" with the drive letter of the hard disk you want to erase.
Press the "Enter" key, type "y" and press the "Enter" key again. The hard disk is formatted.