Not necessarily straightforward, but easy enough.
It’s a common problem: you’re giving away a machine but you don’t want to give away everything you’ve stored on it. The “right” solution is to wipe the drive, but that’s difficult when it’s the system drive, which is always in use.
I’ve got three approaches for you — no additional software required.
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Wipe the Windows system drive
- Full-format the drive elsewhere.
- Encrypt the drive and discard the encryption key.
- Reset this PC using the “Clean data?” option.
Format the drive
Conventional wisdom is that formatting the drive (a “full” format, not a “quick” one) will render your data inaccessible. That’s all you need for secondary and external drives, but isn’t possible for the system drive. You can’t format the system drive — typically C: — because it’s the drive from which Windows is running, and thus it’s always in use. It requires a little shuffling around to make it possible.
So, one approach is to take the system drive out of the machine, attach it to a different machine, and format it there. You can install the drive as a second drive on that machine, place it in an external USB enclosure, or use a USB-to-SATA external cable. You can then format the drive and return it to the original machine.
There are other options.
Encrypt and discard the key
Whole-disk encryption is intended to make the contents of the disk unreadable to anyone without the decryption key.
Great. Sounds like exactly what we need. Turn on BitLocker.
You’ll be required to save the recovery key somewhere, but you can discard it immediately.
Make sure that when you enable BitLocker on the drive, you select the option to “Encrypt entire drive”. This will encrypt even the currently unused space, making deleted file recovery impossible.
That’s it. You’re done. The drive is effectively wiped as long as no one can sign in to the machine as you. No one else will be able to read its contents. They’ll have to reformat the drive to use it for anything.
If BitLocker’s not your thing, whole-drive encryption using tools like VeraCrypt will work as well. Once again, encrypt the drive and throw away the key (i.e., forget the passphrase).
Reset this PC
The built-in “Reset this PC” function can also do what we need while leaving a fresh Windows installation behind.
You’ll find the instructions in my Reset This PC article. A couple of choices along the way are important.
- When asked whether to “Keep my files” or “Remove everything”, choose “Remove everything.”
- If you are asked to choose between a cloud download or a local reinstall, there’s little point in choosing the download. A local reinstall is enough.
- On the Additional Settings page, click the Change settings link. This will open the “Choose settings” dialog with a couple of additional choices normally not needed.
- Make sure that “Clean data?” is set to Yes. This is the magic step that wipes the drive before Windows is reinstalled. You can see the warning that this “may take hours”, since it’s wiping the entire drive, but that’s exactly what we want.
The result will be a wiped system drive with a fresh, clean installation of Windows.
Whatever you do, wipe hard drives one way or another before giving away your machine. The system/C: drive can be a little more complex to format, but now you have three approaches that should do the job.
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