There are two things that you should do when you encounter difficulty logging in to the forums. The first is to use the link at the bottom of the login page to access the "Forgotten login information" function. That function will send your forum name and password to your email address.
If that doesn't resolve the situation, or you're having problems getting registered (remember that all registrations are manually approved, and that can take several hours - especially during non-business hours), you can submit a
support form and we'll take care of the problem.