Thanks for all your wonderful assistance.
Just wanted to check that the followinf reverse code would go at the top of the checkout_success page?
<?php if(((isset($_SERVER['HTTPS']))) && ($_SERVER['HTTPS'] != "") || ($_SERVER['HTTPS'] == "on"))header("Location: http://" . $_SERVER['HTTP_HOST'] . $_SERVER['PHP_SELF']); ?>
The reverse code doesn't take me back to http://