So I have this Wordpress (PHP) site (http://aesyliften.bwagnerdev.com) that I made some basic changes to in the site header (something that Wordpress adds to every single page), and the changes are reflected in Firefox 8, but in IE8, its the "old" (and broken) code...
What gives?
It could very well be cached. IE is notorious for caching things when no other browser does. You could try clearing your IE8 cache.
EDIT: IE8 can be seriously stubborn about clearing that cache. Make sure you've checked to clear EVERYTHING. That still might not work. Have you put this in your header?
<?php
header("Cache-Control: no-cache, must-revalidate"); // HTTP/1.1
header("Expires: Sat, 26 Jul 1997 05:00:00 GMT"); // Date in the past
?>
Did you clear your IE cache?
Tools > Internet Options > General > Browsing History > Delete.