How to Clean Everything Off Your Computer

By Liz Turner

If you plan on selling or donating your old computer, or even giving it to a friend or relative, it's wise to ensure that everything is cleaned off of it. This doesn't just mean sending documents to the recycle bin; such data remains on the hard drive, accessible to anyone with the right software and knowledge of how to use it. The same is true when you reformat your hard drive. To truly ensure your data is secure, a special procedure is necessary to fully wipe your disk.

Things You'll Need

  • Darik's Boot and Nuke or other disk-wiping program
  • CD or DVD-RW drive
  • Blank CD or DVD

Step 1

Download a disk-wiping program such as Darik's Boot and Nuke (DBAN, see Resources). This is a commonly used program for cleaning hard drives and meets the U.S. Department of Defense's standards for disk erasure (see Resources).

Step 2

Burn the downloaded program to disk as an ISO file, which creates a CD or DVD from which you can boot your computer. CDBurnerXP is DBAN's recommended program for burning ISO images to disk (see Resources).

Step 3

Insert the CD or DVD into the computer's disk drive and restart the computer. Upon reboot, a screen will appear that reads "press any key to boot from CD." If this doesn't happen, you'll need to go into your system's BIOS and change the boot sequence so the CD or DVD drive boots first. The method for doing this varies on different computers, but in general you'll press a key, usually "Delete," during startup to enter the BIOS, use the keyboard to navigate to the Boot Sequence menu and use the up and down arrow keys to move the CD or DVD drive to the top spot, above the hard drive.

Step 4

Follow the instructions upon boot-up to run the program. It can take several hours, or even a day, to fully wipe out the drive.

Step 5

Reinstall Windows if desired. If you're donating or discarding your computer, this is not necessary.

Tips & Warnings

  • The only way to completely ensure a hard drive is unrecoverable is with physical means. However, for most people, DBAN or similar methods are more than suitable.If you're planning to discard your computer, be sure you're aware of waste electronics disposal restrictions. Most communities have special electronics disposal days at their landfills or other disposal areas.
  • Be sure you've retrieved all information you wish to save from your computer before performing this procedure.Many people don't realize just how much recoverable, personal data remains on a hard drive after deleting files or even reformatting a hard drive. Important account and identification numbers remain recoverable, and using a method like the one outlined here is essential if you're getting rid of a computer that you've used for online banking, shopping or any file storage.