Problem with install.php

Hi!

I have a problem with installation.

I have the installed apache, mysql and php, and they work correctly.
I have formed wp-config.php with the correct data of the BD, to user and psw, as well as “localhost”.
I can load a page php by means of the navigator.
(Exemple: prueba.php.).
But when position install.php leaves “Error to me establishing to database connection”.

What I can do?

Thanks