DNS error in Explorer but not Fire Fox

I have got 2 website pages loaded on to Dreamhost server, when I put in my domain in firefox they come up ok and everything works.

When I do the same in explorer I get ‘DNS error-can’t find server’.

Also, when I open my web pages on my computer in firefox everything is OK but when I do the same in explorer all the formatting and images are gone, everything is all over the place, it’s a complete mess.

What can I do??

Many thanks

What’s the URL? You can also try clearing IE’s cache: