1. Click "Tools" and select "Internet Options".
2. Click the "Advanced" tab on the right.
3. Under "Browsing", remove the "Enable third-party browser extensions" check box.
4. Click "OK" and close out of all instances of Internet Explorer.
5. Relaunch Internet Explorer.
If it works fine, then incrementally enable individual add ons and until you find which one is causing the problem. Uninstall that one.