Yea, my php is at the very top of the page. I use a $_GET to grab the value of a variable that is passed through the url. If that variable doesn't exist, then i use header() to redirect to the same page, but with the variable. I don't get a specific error for the header(), but i get an error later on in the code because the original variable isn't there.
I was running php on isapi and everything was working great. As soon as i moved to fastcgi, things stopped working.