Can't get db connected PHP pages to work

I have a few sites that are PHP and MySQL. Some of the pages are simply static content, but have the suffix of PHP, so don't need to call content from a database. Other pages that have database served content are not displaying, and also, I am not getting any error messages to help.

Ordianrliy, I develop with ASP, so I have used the IIS-AID installer which installs PHP inside the IIS rather than under apache. I did have my PC set up in the same way previously, but unfortunately, my disk died and I have had to start from scratch and now can't get DB content pages to display.

I have ran the <?php phpinfo(); ?> and I am getting the php details page as proof that php is working.

I have the Server name, DB names, username and password correct in the connections file.

I have just tried double clicking the database in the DW Databases panel and tested the connection there, and I got this message:

"Your PHP server doesn't have the MySQL module loaded or you can't use the mysql_(p)connect functions."

I have no idea what that means, so would appreciate your advice on this.