How To Securely Erase A Hard Drive

People are increasingly storing more and more of their lives on hard drives, SD cards, mobile phones and tablets. Whether it’s family photos, financial and bank details or identification scans, most of our drives contain data that we don’t want to get out there. If you’re getting a new hard drive, it can be tempting to delete everything on the old one, and then sell it. But unless you securely erase it, your files may still be accessible, meaning an old drive can be a goldmine for cyber criminals. Simply performing a standard format will not do. So how do you ensure nobody can access your hard drive’s data?

If you plan on selling your hard drive, you need to securely erase all your data that’s on it using a process known as data sanitisation. Simply moving the contents of the drive to your recycle bin, or formatting it, will not suffice, and anyone with a basic knowledge of data recovery will be able to get your data back. When you remove files, it doesn’t actually get rid of the data, only the index entry that points to it. The file system won’t recognise the data as being there, so many people assume it’s gone for good – but this isn’t true. Until the operating system overwrites the drive with new data, your files and folders are still recoverable. While this is useful in the event of an accidental deletion, meaning you can restore your files, if you’re selling your hard drive, this won’t do.

Disk-wiping refers to a non-destructive method of sanitising your hard disk drive. A good free piece of software to do this is DBAN, or Darik’s Nuke and Boot. This free data destruction program erases all data on a hard drive and overwrites it with dummy data. This will ensure that your data will be non-recoverable, and you won’t be the victim of cyber criminals. An even better option, if you’re not selling your hard drive, is to physically destroy it using a hammer or granulator.