I have a user that can't seem to login. If the user tries to login with their user name an error returns "Invalid user name". As admin I was able to view his profile and confirm that his user name is registered. If the user logins with his email he gets the "Welcome back" greeting but it doesn't log him in. He still sees the option to register and login. We have a little over 10,000 user and he is the only one that is having this issue.