33586 HTML email in PHP

Hello, I need someone to fix my script that it sends html in emails. Right now it sends the mail fine and collects all the info, but i need the message to be in HTML format so that links work. Right now, it works fine with hotmail right now but its not working with outlook. I just need some to add the right headers to the script as i think that is all its missing. Quick, easy project for a good review. Thanks!