PHP referer url and redirect
<p>I can't seem to work out why the below sends ALL traffic to the page-not-found page, even if referred by Paypal. Any ideas?</p>

<pre><code>$refererUrl = $_SERVER['HTTP_REFERER'];
$Exploded = explode("/",$refererUrl);
$urlToCheck = $Exploded[3];
$findURL = strpos($urlToCheck,'paypal.com');
if($findURL === false){
    header('location:/page-not-found');
} else  {
/* Do something if page referred to by Paypal */
}
</code></pre>
