This is a small example I just tried out and I can't find the error you encountered:
File: Test.html
<html>
<head>
<script type="text/javascript" language="javascript">
</script>
</head>
<body onload="">
<h1>Hello world</h1>
</body>
</html>
This is the file that loads the former file:
File: LoadDiv.thml
<!DOCTYPE html>
<html>
<head>
<style>
</style>
<script src="http://code.jquery.com/jquery-1.5.js"></script>
</head>
<body>
<div id="myTip" class=".div">This should be replaced with something from a file!</div>
<script type="text/javascript">
function loader()
//alert("Hello!");
$("#myTip").load("./Test.html");
}
window.setTimeout(loader, 1500);
</script>
</body>
</html>
What are you getting if you call up the URL of product.html? Does it display correctly on its own?
Cheers!
-MRB