How do I remove an identity if I don't know the password?

Tech-Archive recommends: Fix windows errors by optimizing your registry

I have a user who, at some point, forgot her password. She set up a new
identity and then tried to remove the password. Which she could not do
because she did not know the password. At which point, she contacted me. I
have removed and reinstalled OE without success and am looking for the most
appropriate way to complete this task.

Thanks!
.