If you decide to sell on your old computer or laptop then it’s important to delete all of your old files and programs before you do.
A lot of people think that simply re-installing Windows is sufficient, but this is definitely not the case. It’s really easy for your computers new owner to recover all the files and folders that you thought you’d deleted, the only way to ensure that your files stay gone is to use a program like DBAN (Darik’s Boot And Nuke) to securely wipe all of your personal data.
You then need to insert your CD or USB stick and then reboot your PC, you should see a screen like the following:
Once you’ve gotten to the above screen you have a number of different options. Pressing F3 will give you a list of commands that you can use for different types of hard disk erasure. You can also press Enter at the command prompt to enter the graphical interface.
However, for most people the “DOD” (Department of Defence) standard will be enough.
To wipe your hard disk to this standard just type “DOD” (without the quotation marks) and then press Enter. Your computers hard disk will be securely wiped so that no data can be recovered. While this happens you’ll see the following:
This will take some time, but once complete you will be able to rebuild your PC with the original operating system disk. It’ll then be completely safe to sell on your PC with no fear of your data being compromised.