I use a laptop as my primary machine and when I'm in the office I have a second monitor hooked up to a dock so that I can work on dual screens. Sometimes after I undock (therefore switching back to a single screen) Windows remembers the last position of whatever I had open...if that happened to be on the second monitor then the next time I open it Windows renders it right where it was before - off screen! There it is in the task bar; I can minimize it or restore it but I can't see it.
Disregarding the sometimes oddball suggestions I've seen in forums, groups, and even magazines about how to fix this, I found a simple key combination that works:
- Make the window active by selecting it in the task bar
- Ensure the window is not maximized by pressing alt-space (that's the alt key and the spacebar at the same time), then press r.
- Move the window back on screen by pressing alt-space, then press m, and then repeatedly press the arrow keys to move the window back on screen. (tip: after pressing any arrow key just once you can use the mouse\touchpad to move the window)
Hopefully this saves you some time and frustration next time it happens to you.