You're trying to access the MySql local server on your machine or something else? and I think you've changed the default password or you didn't specify that you're using a password..
OK. Can you tell us what it is you're trying to access? so we can help you with the problem. if it was MySQL local server, then I want you to open these files: Wamp-->alias--> phpmyadmin.conf... and tell me what you've got in the phpmyadmin file..