According to this article, you can securely erase a disk by following these steps:

  1. Perform full drive encryption with BitLocker
  2. Format the drive
  3. Encrypt the drive again.


The second encryption ensures your first encryption key - which is usually kept on the drive - is overwritten. A zealous decrypter could recover the key and decrypt your data. But with the second encryption they can only recover the second key, and, since the older data is also encrypted, they still can't read it.

I wish to hear second opinion before I rely completely on this method. I have spare SSDs I can sell on the second-hand market. Would you sell a drive that was encrypted two times to someone you don’t know?

  • Many good questions generate some degree of opinion based on expert experience, but answers to this question will tend to be almost entirely based on opinions, rather than facts, references, or specific expertise.
    – Ramhound
    Jan 31, 2020 at 22:12
  • 1
    One overwrite pass (entire spinning disk) with zeros will make Any data on the hard drive unrecoverable. More is a waste of time. SSD's are a bit different>>>superuser.com/questions/22238/…
    – Moab
    Jan 31, 2020 at 22:24
  • This supports the @Moab comment. It also talks about Peter Gutmann's original paper that started all of this nonsense in the first place. Jan 31, 2020 at 22:32
  • In my question I specifically mention encryption. Would you sell a drive that was encrypted twice to people you don’t know?
    – Jam
    Jan 31, 2020 at 22:42
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    A lot of modern SSDs already use encryption internally. In that case you can simply execute the "Secure Erase" function via the manufacturers utility and the SSD throws away the encryption key. That is very fast and provides even more security than overwriting it (because you can never overwrite every flash cell of an SSD).
    – Robert
    Feb 1, 2020 at 11:54


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