Iím not sure why itís doing it, but the encoding for the page (View..Encoding) should be set to Western European (Windows), but on yours itís being changed to Unicode-8. You can manually change it back, and the problem is gone. That it will still be a problem for others remains.
I can find nothing else different in the actual code thatís being sent from your server. For some reason IE is not following the Content-Type meta tag on your pages.