Icons not displaying

I've deployed a web page with the file vista control, and the tree and controls are there, but the icons don't display (red X).

Update:  allowing session cookies did not help.

This is a known problem effecting many IE users. You need to fix PNG mime type settings in the registry.

Please try the reg file fix in this article:
[link:{http://www.winhelponline.com/articles/202/1/PNG-images-are-not-displayed-on-Web-sites-in-Internet-Explorer.html
}:{PNG images are not displayed on Web sites in Internet Explorer}]PNG images are not displayed on Web sites in Internet Explorer[/link]