Darik Boot and Nuke description
Darik's Boot and Nuke (

Darik's Boot and Nuke ("DBAN") is a self-contained boot floppy that securely wipes the hard disks of most computers. DBAN can automatically and completely delete the contents of any HDD that it can detect, which makes it an appropriate tool for bulk or emergency data destruction.

DBAN is a means of ensuring due diligence in computer recycling, a way of preventing identity theft if you want to sell a computer, and a good way to totally clean a Microsoft Windows installation of viruses and spyware. DBAN prevents or thoroughly hinders all known techniques of hard disk forensic analysis.

Usage:
Double-click the exe program to install DBAN to a floppy disk or USB flash device.

You must use an account with full hardware access to create the DBAN boot media. This means that you must be a member of the administrators group or have similar privileges on your Microsoft Windows computer. Virus scanners and domain policies can prevent you from creating the DBAN boot media.

The USB booting capabilities of many computers are incomplete or broken. Most computers capable of booting from a USB device require that it report a removable media type, and that it be unpartitioned and smaller than two gigabytes (so that the BIOS can boot it like a floppy disk).

If the drive letter of your USB device does not appear in WinImage drive list, then it is an unsupported media type. In particular, most USB+IDE bridge implementations are unrecognized, which means that a 2.5 inch hard disk in an external USB enclosure is incompatible.