mnelized on "WP-admin 404 error"

UPDATE: I read from another thread how someone had the same problem as I do. Whenever he tried to login using an admin account, he also gets a 404 error, however, when he tried to login using a contributor account, he can see the dashboard perfectly. Tried to do the same and it worked! However, I really need to fix my admin access. Anyone have a good idea what's going on? Thank you!