can’t start the install.php

hello,

i’ve got php 4.0 installed and mysql with mysqlcc(controll center).
in mysqlcc i can see that there is a connection but when i look in my infoscreen(on the right) it says: connection no.

every thing is set up how they say in de guide.
the wp-config is also edited als he should be with(wath i’m sure of) the right information.

so if i start the install.php it keeps giving this error:

Error establishing a database connection
This either means that the username and password information in your wp-config.php file is incorrect or we can’t contact the database server at localhost. This could mean your host’s database server is down.

Are you sure you have the correct username and password?
Are you sure that you have typed the correct hostname?
Are you sure that the database server is running?

also i’m working on MS windows 2003 server and i am the administrator of it.

could anyone please help me out here?!?!