index.php won't display in IE 6, 7 and 8

I developed several typolight websites (on the same server) which worked just fine in IE, Chrome, Safari and Firefox. But with my latest typolight website I get a strange error that only occurs in Internet Explorer 6, 7 and 8. When I load the homepage it gives me an 404 page (the standard IE 404 page, not the Typolight 404). But when I load index.php/home the page will display correctly in the IE's.

What goes wrong?

Regards,
Telemachus

Solved the problem. On the first page of my website (a website root page type) I checked the option 'Language fallback' under DNS-settings and entered the language (nl in my case). And now the index.php is shown in the IE's!

My Safari and Firefox are dutch translations, and my (emulated) IE browsers are english. When a friend viewed the page from a dutch translation of IE the page worked correctly, so it had to be something with language.