Hi Genem56,
I'm not sure if I understand you correctly, but do you have Internet Explorer installed, or have you just been using MSN as your browser? Also, what's SBC? Sorry! :-[
You should just be able to uninstall MSN with Add / Remove programs in your Control Panel, then, if you haven't already, you can install Internet Explorer.
If this is an ISP branding problem, like Sandra suggested, you might want to
click here for a handy guide to all things IE. There is a section
here for removing ISP branding, but it does involve a journey into the registry, which I would only advise someone to attempt if they have some experience.
Hope that helps, but please come back to us with some more details.