I love large work spaces! My home office features 3 large 20 inch monitors (and I need them). When I leave my duly appointed castle, I travel with my well worn Acer wide-screen laptop. Upon arrival at a work site or office, I immediately seek out a spare monitor with which to tango. Thankfully Windows makes it easy and painless to double my workspace.
All this monitor transversing does have a few problems though. The most irksome is windows thoughtlessly floating in a phantom monitor. The Windows OS, being helpful, leaves these windows and dialogue boxes where you left them (on a monitor no longer present), rendering you quite helpless.
Here’s a remedy that works most of the time.
1) Select the window any way you can. (Alt + tab often does the job, but windows are selected by default when they are first called up).
2) Use the key combination alt + space to open up the window controls dropdown (this will happen out of view, so you won’t know that its done anything)
3) Now press M on your keyboard.
4) press any arrow key.
5) Move your mouse cursor (do NOT click it) around your visible workspace until the window appears.
You can see how this works by experiment with a window that is not in full screen mode that is in your view port. This very useful technique took me hours of frustration to find and i still use it regularly.