Have you tried reinstalling Internet Explorer 7?
I would uninstall IE7, delete the registry keys associated with it (be careful; you may want to use a program to get rid of these entries, CCleaner or WiseRegistry, for example). And then reinstall it. I’ve heard of the Windows Genuine Advantage Validation Tool doing this a few times, so you may want to update your computer to get the latest of that as well.
Hope this helps!