Have you been using dual screens?
http://cybertext.wordpress.com/2008/04/07/lost-your-windows/
See www.grainge.org for RoboHelp and Authoring tips

@petergrainge
I can see it now! Although, I don't think it was the fix provided in the link you sent Peter that fixed it. I did the steps suggested and no go. I then stumbled upon this thread by you at http://forums.adobe.com/message/4502519 where you fixed the problem, and after trying out the fix - out of the blue, I see my Topic List pod in the upper left corner of the screen as small as an icon. As soon as I maximized that, it was back! Perhaps it was a combination of the two fixes, but when I did the steps in the suggestion above, it would only show the programs, not apps/windows/pods within the program. Regardless, I'm back in business. Thank you Jeff and Peter for your expertise on this - I appreciate it! 