Installing PHP

Hello, I'm newbie and I'm trying to install PHP with Apache, but it doesn't work. Every time I try to run a test I receive the message "Not Found The requested URL /php/php-cgi.exe/test.php was not found on this server." OR (when I try to change some options) "Forbidden You don't have permission to access /php/php-cgi.exe/test.php on this server." I've tried to copy the recommended configurations from some sites, but it haven't worked. The machine runs Windows XP, I'm using an administrator account, no firewall is blocking me, PHP and Apache are the most recent versions. Thanks in advance.