Shows code instead of info when calling PHP from Ajax

Dear people, I've installed Apache Server 2.0.59 and PHP 5.2.4 in my PC (Windows XP). And everything is good, phpinfo shows all the info, and my PHP scripts work fine. Everything’s works fine BUT the following: I have this html page with Ajax and a form that when submitted calls a PHP that updates the page. Well, when I click the submit button instead of having the PHP updated information, I get the PHP code character by character. I've searched the Internet for more examples of forms calling a PHP page through Ajax and I have the same problem with all of them, I get the code every time!! I don't think it is a problem with my coding, not only I've been trying more examples but also I got my code checked and it is correct. Then, it has to be a configuration error, but I cannot find which one it is .. somebody please give me a hand, I'm lost!!! Thanks in advance! --------------------------------- Looking for a deal? Find great prices on flights and hotels with Yahoo! FareChase.