Hey all, we are having a big issue... when a user buys one of our products at www.baselinesoftware.com, on the thank you page with their order number the source code ends here

<h1 id="checkoutSuccessHeading">Thank You! We Appreciate your Business!</h1>
<div id="checkoutSuccessOrderNumber"><strong>Your Order Number is:</strong> 10603</div>
<div id="checkoutSuccessMainContent" class="content">
There is nothing after that. It seems like define_checkout_success.php isn't even loading... which is a big problem because theres loads of code on there we need. Does anyone know why this could be?