This section addresses one common error message that you might encounter when testing a PHP database connection to MySQL 4.1: "Client does not support authentication protocol requested. Consider upgrading MySQL client."
You may have to revert to an earlier version of MySQL, or install PHP 5 and copy some dynamic link libraries (DLLs). For detailed instructions, see Installing a PHP application server (Windows) in Getting Started with Dreamweaver.
Also see the following TechNotes on the Macromedia website: