Running Windows 8.1. When I'm in the Metro experience (the Start menu, the Settings screen, or even Internet Explorer, for example) the touch screen works perfectly. When I'm anywhere else -- on the desktop, running Excel, etc -- I can see the screen registering a touch (it "splashes" when I touch it) but no action happens. If I tap on an icon on the desktop I see the "splash" but the icon isn't selected. I can't drag a window, launch an app, or control a button on a dialog box. Happens even in Safe Mode.
Ideas?