Browser caching older flash site

The client’s old site was Flash and was hosted elsewhere. Domain:

New site is WordPress and hosted with DH. Domain:

I change the DNS for When I set up the domain in the DH CP I simply redirected it to

However, when visiting the browser (Firefox PC, Chrome PC) continues to use the old Flash site from its cache. An F5 forces the redirect but I obviously. can’t expect everyone to know that.

How can I ensure that anyone who visits will end up at and not get stuck seeing the old Flash site?

Thanks in advance for your help.

try this php code in your page for a while

<?php header("Expires: Mon, 1 Jul 1000 05:00:00 GMT"); header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT"); header("Cache-Control: no-cache, must-revalidate"); header("Pragma: no-cache"); ?>