I have been playing Skyrim with Win 8.1 and no problems. After not playing it for awhile, I find that it just doesn't work. I sign on to Steam and click Play and the introductory window shows and the first few notes of the theme song and then it just disappears! No explanation or error messages. I uninstalled and reinstalled with the same result. Any help will be appreciated!

Have you contacted Steam support? They take a long time to answer, but they do follow up.

You might check if this is the problem
https://www.reddit.com/r/skyrim/comments/41b5y2/skyrim_launcher_has_stopped_working/