1. Install PHP, you can download it from http://www.php.net/downloads.php
2. Open the configuration of Quick 'n Easy Web Server and select the CGI tab.
3. Click Add, enter PHP for the extension and c:\php\php.exe for the interpreter (c:\php\php-cgi.exe for PHP5).
4. Click OK to save.
5. The server now executes PHP scripts.
Note: if your PHP application uses MySQL databases you also need to install MySQL: http://dev.mysql.com/downloads/