“I have several old computers that I’d like to donate to school charities,” one reader wrote in an email. “I have erased the information on the hard drive, but have heard that simply deleting data does not remove it completely. Can you tell me how to securely erase data from a computer?”
Unfortunately, they heard it right: Just because you deleted a file on your computer and emptied the Recycle Bin, doesn’t mean it’s gone forever. Making sure those files are properly gone takes some extra work, but if you’re considering donating, selling, or even recycling an old computer with a hard drive, it’s definitely worth putting the time into it.
“There are so many stories of people buying used computers online and recovering data,” said Andrés Arrieta, director of consumer privacy engineering at the Electronic Frontier Foundation. “It’s pretty scary. It’s your whole life there.”
If you’re serious about keeping your data from potentially prying eyes, here’s how to securely erase your old hard drives.
For hard drives in a working computer
If you can actually boot and use the computer you’re trying to get rid of, consider yourself lucky. Fortunately, with the right software, the process can be simple. Fortunately, in some cases the operating system the computer is running already has everything you need to securely erase the hard drive.
- Click the Settings icon and then click “Change PC Settings”
- Click on Update and Restore, followed by “Restore”
- Under the Remove everything and reinstall Windows heading, click “Get Started”
- When prompted, select the option “Completely clean the drive”
- Click the Windows button in the lower left corner and then the gear-shaped Settings icon
- Click Update & Security and then “Recovery” in the sidebar
- Under ‘Reset this PC’, click ‘Get started’ and then ‘Remove everything’
- When you get to the “Additional Settings” screen, click on “Change Settings” and make sure the “Clean data” and “Delete files from all drives” options are enabled
- Click the Windows button in the toolbar and then the gear-shaped Settings icon
- Click on Windows Update. Then click on Restore and select Reset PC option
- Choose “Remove everything” and click on “Change settings” to ensure that the “Clean data” option is enabled
For computers running even older versions of Windows — like Windows XP, Vista, or 7 — you may have to go elsewhere for the right tools. The EFF also recommends using free apps like BleachBit and DBAN for securely erasing individual files and entire hard drives, respectively.
These may also come in handy if you’re also using more recent versions of Windows. These apps are great for dealing with particularly sensitive data that you want to get rid of, or when you want more control over how your hard drive is erased and overwritten.
- Turn on (or restart) your Mac and hold down the Command and R keys while it boots up – this will put your computer into recovery mode
- Log in to your account (if necessary) and click Disk Utility
- Select the hard drive you want to erase and click the Erase button
- Click Security Options and select how thoroughly you want to wipe the drive. Most people are fine with selecting the second option, which will overwrite all your saved data twice
For hard drives in a non-working computer
If one of the computers you want to dispose of responsibly won’t turn on, it may be a better fit for a visit to a recycling facility than an eBay buyer. But just because the thing won’t boot doesn’t mean the personal data stored on the hard drive has been lost for ages.
We’ll have to do something about that. And the first step is accessing the hard drive itself.
For those familiar with the insides of a computer — or anyone willing to poke around in it — one approach is to crack open the PC and grab that hard drive. Don’t worry: often enough, this is much easier than it sounds.
Most desktop computers can be opened quickly, and assuming there aren’t a lot of parts getting in the way, disconnecting the hard drive shouldn’t be much more than unplugging some cables and removing a bracket. This process can be trickier for laptops, so it’s a good idea to look for a repair guide or YouTube tutorial for your particular model before taking the plunge.
Once you’ve managed to free that hard drive from its metal prison, use a USB drive enclosure or docking station to physically connect it to another computer, where you can use the aforementioned software tools to responsibly clean them up. to clear.
If this sounds annoying, there’s always an easy way: you can take your machine to a local repair shop where they can remove that hard drive in no time. (Despite all its quirks, Yelp is a handy place to look for these stores.) They can probably erase it for you safely too, which would save you even more time.
The Office Space Approach
There’s also the low-tech — and some might say more therapeutic — approach. If you can physically remove your old hard drive from a computer you plan to recycle anyway, take the drive outside and put a good dose of sledgehammer on it. A rock from your yard would also work, as would using a drill to make four or five large holes around the center of the hard drive.
Really, go with what feels right when the name of the game does some Office Space-style damage. (Just don’t forget the safety glasses.)
“If you’re going to just throw it in the trash, hit it,” Arrieta said. “Why not have fun with it?”
Specifically, what we’re trying to do here is contaminate the disks of the disk, the spinning disks on which our data is minutely, magnetically placed. Destroying these platters doesn’t always make your data completely unrecoverable, but it makes the process of rescuing all that information more trouble than it’s worth in all but the most extreme cases. (For example, if you’re holding government secrets, you’d probably be better off destroying the drive altogether.)
But once you’ve had your fun, don’t just toss that broken drive in the trash — find a local e-waste facility and drop the carcass there.