I tried to log in to a database through phpmyadmin. I must have entered the wrong password and I got a "Cannot log in to the MySQL server" error. I then carefully entered the correct account and password and still got the same error. JF of sysadmin suggested I fill in the account name and password and then force-reload the page, then fill in the password and try to log in. That worked, though neither of us really understands why. It must be something to do with session variables.