Do you mean the username and password you use to create a MySQL Connection?
Or a username and password for a user that you have registered through the registration page?
you wont be able to log in using the MySQL User name and password, you will need to register a user through the registration page.
We need more information to be able to tell what is wrong:
What page does the login page direct to if login is correct?
What page does login direct to if it fails?
My Guess is that it directs to noaccess.php on failure.