Why did my Norton 360 Identity Safe quit working?

I have used the product for almost two years. Suddenly, it quit coming up on my Internet Explorer screen. I went to the main screen, pulled it up, turned it all to on, and (cold) rebooted it twice. Still no menu line on the IE. So I checked at the Norton forms, but no one has had the same problem. Has anyone got any idea of how to fix it?