- Do you have recent versions of PHP and MySQL installed? MySQL 4.1 is recommended at the moment, along with PHP 5 if you can get it.
- Are you having a password hashing issue? I have written about diagnosing and resolving this at my FAQ.
- Do you have a proper user and database created with appropriate permissions for the user?
- Have you checked the MySQL error log?
This was first published in June 2005