For no particular apparent reason, or having done nothing to system outside of normal Windows Updates, my Gadgets stopped displaying on desktop. Here are the observations:
1. When I right click the desktop, I am unable to uncheck the Gadgets selection.
2. When I right click the desktop, and click the "view" dialog, I am UNABLE to UNCHECK "Show desktop gadgets".
3. When I go to the CONTROL PANEL and select "Appearance and Personalization", I am UNABLE to select any choices under "Desktop Gadgets". Clicking on these are totally UNRESPONSIVE. Only the "Get more gadgets online" will launch the web browser to the web page that says gadgets are no long available in Windows 8.
Virus scanning and spyware scanning show nothing.
Note MS offered this advisory almost two years ago
http://technet.microsoft.com/en-us/security/advisory/2719662
I'm just guessing that if you did not disable the Gadgets back then, some recent Update must have done it for you.