Re: Prblem upgrading
I don’t know the proper way to fix this. Is the user in the database someone you created or is that someone else? If it is one of your users, I think I would change the email on that account and then request a password reset for that account. Then you can change the password and change the email back. That would only help if the user is a keymaster/admin. If not, this will not help.
There used to be a way to create a new keymaster account by adding a line to the config.php (now bb-config.php).
I would backup your database first because I have no idea what this actually does and I don’t want you to lose anything.