1. Create another Admin account then change the other admin account there.
2. Don't enter anything for the password when changing it, leave blank.
3. Item 2, try it in SAFE MODE
4. Forget all that and clear it with NTPASSWORD (free, plenty on the web on how to use, stopping here.)
Bob
I've had no password on my Win 7 machine for years. I recently created one as an administrator because I had some guests over. Now I want to go back to no password. Windows says, "Windows is not able to change your password". Huh?

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