I am constantly warning people not to sell on hard disks without doing the proper procedures. For me, the required amount would be to smash it up with a large hammer. However, if you’re selling it on, obviously that’s not a practical idea. In this post I will explain how to prepare a hard disk to be sold on, and that is not to format it.
Firstly, you’re going to need to get DBAN (Darik’s Boot and Nuke, surely one of the best apps in the world) from its official site. If you’re not quite sure what to download, don’t panic. Just click on the applicable link to your boot media. That will direct you to a download page, where a file will be downloaded to your computer. If you have selected the one to do it via a floppy disk or USB flash drive (I beg of you not to do the USB flash, as I have never tried it and I have heard it is not particularly good), merely execute the program and it will guide you through the recommended steps (then skip to the paragraph after next). For the CD/DVD option, you will find that you have downloaded an ISO file. An ISO file is basically a group of files that are preconstructed, ready to be put on a disk immediately. To burn it to a CD/DVD, get CDBurnerXP, a program that is surely better than Nero or MagicISO, and it’s completely free, too.
Open up CDBurnerXP, select ‘Create Data CD/DVD’, then click on the ‘File’ menu. Then select ‘burn disc from ISO file’. Once the ‘Write ISO Image’ dialog appears, click on the browse button (the one with the three dots) and find the ISO file you downloaded, then click OK. After that, click ‘burn disc’, and your disc will begin burning. Don’t worry about fiddling with any other settings.
Once all of that is done, insert your disk into your computer. If any windows appear asking you what you want to do, just close them. Leave that disk in and restart the computer. As your computer restarts, it should detect your CD/DVD/Floppy and start the program. It may say ‘Press any key to run CD’, in which case do as it says. If, however, no prompt appears and it loads Windows, restart again and enter your BIOS. This may sound challenging but actually it is very easy, just look for something that says ‘Press [key] to enter setup’ or ‘Press [key] to enter BIOS’ or similar, and press the key (there may even be an option to select boot device, in which case tap that and select the medium you want to use. Usually it will show the brand of the boot device in the name, if not, try going through them until you get the right one, rebooting after each attempt to regain you access to the screen.). Then your BIOS will come up. Now, this may look confusing, but it is very easy. Keep pressing the right arrow key until you get to the arrow that says ‘Boot’ or similar. Then go to ‘Boot Device Priority’ or similar by going up and down the list, and then pressing enter. There should be a number of them, but go to the one that says ‘Primary Boot Device’ or ‘1st Boot Device’ or similar, and select the device you want to use. Usually it will show the brand of the boot device in the name, if not, try going through them until you get the right one, rebooting after each attempt to regain you access to the screen. Make sure, however, to put the item that was the primary before into either a free slot, or the slot where the item you selected before used to be. Now, go to exit (you may need to press esc first, if pressing the right arrow key does nothing) which is usually the last option, keep pressing the right arrow key until you get to it and select ‘Exit and Save Changes’ or similar. Your computer will then restart, and it will boot up the media that has DBAN on it.
Once DBAN has loaded, you will be presented with a screen that looks like the one to the right. Press F3 on your keyboard to see the commands that you can input, but don’t select the ‘autonuke’ option, or press the enter key, as this will not wipe your data enough so that fraudsters and other prying eyes can’t get to it. Once you have pressed F3, you will be given the commands that can be used with DBAN. DoD is a method which the Department of Defence in the USA use to wipe their computers, and it is pretty good, but the Gutmann method is much better, and if you use that fraudsters won’t have a chance in hell of getting their hands on any of your private data. I would always say to use it as it is practically impossible for any fraudster to access your data if you use it. So, just type ‘gutmann’ without the quotes. Then the wipe will begin.
Once the wipe is finished, you will be told to shut down. Make sure to remove the disk before doing, if you still have it in. And voilá, your disk is erased, and ready to be sold free of any remnants of any data that may have been left behind if you had merely formatted it.