Okay I understand now.
For anyone who is still trying to figure this out, here’s what the problem is:
This is what header.php looks like when downloaded.
<link rel="stylesheet" type="text/css" href="wp-content/themes/Iridium/style.css"/>
<!--[if IE]>
<link rel="stylesheet" type="text/css" href="wp-content/themes/Iridium/ie.css"/>
It should be
<link rel="stylesheet" type="text/css" href="/wp-content/themes/Iridium/style.css"/>
<!--[if IE]>
<link rel="stylesheet" type="text/css" href="/wp-content/themes/Iridium/ie.css"/>
You need that slash before the wp-content to signify that it’s a relative location.
=]