Can't Connect to database

I have just installed the opencart and trying to setup. When i enter the info for the database connection i get an error can't connect to database. I downloaded the cleaned up opencart.SQL and left it in the install folder. Is the error because i don't know the username and passwoed perhaps ?

Wil

Your password or database name might be incorrect please check the config files in both admin and you cart root.

Phil.