This tutorial explains how you can set, change and reset (if you've forgotten the password) MySQL root passwords. Time and again I see problems like mysqladmin: connect to server at 'localhost' failed error: 'Access denied for user 'root'@'localhost' (using password: YES)'. So I thought it's time to remind you how to solve MySQL related password problems. If you are just looking for a quick fix how to reset a MySQL root password you can find that at the bottom of this tutorial.
Read the full thing at http://www.howtoforge.com/setting-changing-resetting-mysql-root-passwords