Wipe Hard Drive Clean Using Free Software
Selling your computer but worried of somebody trying to get a hold of your personal information? As some of you know, whenever a file is deleted from the computer, it does not really gets deleted but rather the opearting system identifies the space as available so it can be re-recorded again. This is a huge problem since your hard drive can fall in the wrong hands. In this article I will cover my favorite method for wiping a hard drive clean, a method that is reliable and can even be run under Windows using Virtualbox.
There is a free program for this purpose which everybody seems to prefer, however, I do not. That program is Darik’s Boot and Nuke (DBan). Dban seems to have terrible USB detection capabilities. Fortunately, there is a better solution. Parted Magic offers you several options. Some are meant to be a quick solutions and some like nwipe (a fork of dban) are for the paranoid. However, all of these options will make your data unrecoverable, regardless of the one you pick.
Using USB vs. SATA Controller
It is important to mention that, as convenient as connecting your hard drive by USB is, it is always faster to connect the hard drive directly using either the computer’s SATA or IDE cables. Bear this in mind before starting to wipe a large hard drive, or you might end up waiting days rather than hours.
WARNING!: When working with any of these programs, make sure you have the correct hard drive selected. Once you wipe the hard drive with any of these methods, your data will be unrecoverable!
Instructions
Download the Parted Magic ISO image and burn it to a CD.
Boot your computer with Parted Magic’s LiveCD. Make sure your CD-ROM is set as first boot device in your computer’s BIOS.
Click Parted Magic start button, click on “System Tools” and “Erase Disk“.
This will bring up the “Disk Erasing 101” window, which will give you several options to pick from.
Using Dd disk, Ddpart, Shred or Secure Erase Command
Dd disk, Ddpart, Shred and the Secure Erase command are all meant to be quick solutions. If you are in a hurry to wipe your hard drive and don’t want to wait several hours, these are the solutions for you. They are safe enough to keep your data out of the average “wrong hands” but they are not as secure as nwipe, which I will be discussing in the next section. However, going into which method is more secure over another is not the purpose of this article. If you would like to know more about how these methods work, read this article by Peter Gunntman, the leading authority in the field.
The instructions to start Dd disk, Dd part, Shred and the Secure Erase Command are pretty much the same. The following set of instructions apply to all except nwipe. For instructions on how to use nwipe, go to the next section.
Once you have the “Disk Erasing 101” menu open, select any of the methods previously discussed and click “Continue“.
On the next window, select the drive you will be wiping. Be 100% sure of the selection you make, or you will probably end up wiping a different drive. Once the wiping process is started there is no going back; your data will be lost. Click “OK” to continue.
Next, you will receive a warning asking if you are really sure of what you are doing, if you are, click “OK“.
The wiping process will begin immediately after clicking “OK” without any further warning.
Nwipe Instructions
If you are truly paranoid about the data you have in your hard drive, Nwipe will give some peace of mind. Nwipe uses the most advanced and secure wiping techniques. It is a fork of the famous Dban and offers pretty much the same capabilities.
Contrary to the previous options we just discussed, Nwipe requires an existing accessible and readable partition, otherwise the drive will not be detected. Parted Magic must be able to see and access the drive. If the drive does not have a filesystem, Nwipe will not detect it. To check this you can either click on the icon named “Mount Devices” and see if it comes out on the list of devices to be mounted, or click on “My Documents” and see if it appears on the left hand side column.
To open Nwipe, select it from the “Disk Erasing 101” menu and click “Continue“.
Using the UP and Down arrow keys on your keyboard, navigate to the drive you want to wipe and press the “Space” bar to select it.
Nwipe comes without any instructions, at least not the version that comes with Parted Magic. It does not even state the keyboard shortcuts to press to start the wiping process or to change the wiping method. I had to figure out how to use it by pressing each key on the keyboard. Very unusual, but fortunately I was able to figure them out. Here they are:
WARNING! Nwipe (just like Dban) does not give you any warning before starting to wipe the drive, so be really sure you have the correct drive identified and selected before starting the wiping process!
Nwipe Keyboard Shortcuts
Shortcut | Action |
F10 | Start wiping drive |
p | Pseudo Random Number Generator (PRNG) |
r | Number of rounds |
v | Check if the drive is actually empty |
m | Wiping method |
Before starting, make sure you have all the desired settings in place (you can use the defaults) and press “F10” to start wiping your drive.
Windows Won’t Detect My Hard Drive After Running Nwipe – What to do
Each hard drive comes with a low level manufacturer’s partition table (not to be confused with the actual partition type: FAT32, NTFS, EXT3, etc.) Windows needs this partition table in order to “see” the drive. Make sure you create this partition table before using or giving your drive to someone else, or that person will have a hard time determining what is wrong with the drive.
To create this partition table, open the “Partition Editor” (Gparted) on Parted Magic’s Desktop and select the drive you just wiped. On the top menu, click on “Device” and then on “Create a partition table“. Select the partition table type depending on the operating system you will be installing or just click on “Apply” to select the default (MS-DOS) if you are using a Windows operating system.