How can an operating system be safely removed from a machine?
If you're donating, selling, trading or otherwise disposing of a Windows computer or computers, securely removing the operating system and data while leaving the hardware intact is an important step that's often overlooked.
You have a couple of options for doing this. The most straightforward and secure method is to use a tool like Active@ KillDisk, which will securely wipe every sector of the drive. You simply download the tool, put the bootable image onto a CD-ROM or USB drive, and then boot your computer and step through the wiping process. This process can take an hour or longer, depending on the speed and size of your hard drive.
Another alternative is to restore the factory image to the computer. You may have this on a CD, or it may be loaded in a special partition on your computer that's accessible via "factory restore" software, which has been installed in Windows. Search through your Programs menu and the image is typically in a folder named after the computer manufacturer.
If you have this software, step through the restoration process and it will remove the partitions (the important part to ensure secure deletion), and then format and reload the operating system back to the factory default.
It doesn't matter whether you have a personal or business computer. You always need to wipe or reload a Windows machine before letting it go. By taking these steps, you can be sure that sensitive OS configuration information (i.e. login passwords, VPN connections and software activation keys) and personal information (i.e. files, search history and passwords cached in Web browsers) are properly kept from curious eyes.
This was first published in June 2014