I haven't seen this before, and I don't know what would have caused it. Repairing/reinstalling IE should have fixed it. The only thing that I can think of is that maybe your computer is infected.
If you are in a bind, and need a browser to use NOW. Use
FireFox so that you can do what you need to do right now.
Later today someone else may be able to help. Someone who has seen this sort of problem before. In the meantime, when you have time I suggest that you post in the
Spyware Forum, and confirm that your computer is not infected.
Sorry that I couldn't be of more assistance, but you can use FF to get you by for now. If you use sites that require IE, you can install an IE Tab from
here. After installing the IE Tab > Open FF > click "View" > Toolbars > Customize > Drag 'n Drop the IE Tab to your toolbar for easy use.