When I drag a window I cant see it, it just kinda disappears with a negative when I resize or drag a window. I was just wondering why this is, it used to be fine. Did I change a setting? Anyway the pic shows the box when I drag and when I let go the window snaps to the box.
Just to add to Ted's perfect answer, if the box for "Show Windows Contents while dragging" is already checked, just uncheck it and then check it, click Apply, then Ok.
There are some programs, not very many, that will for some reason disable the show windows contents while dragging, on mine for instance, it's my EaseUS Partition Master Pro, every time I open the program, and the only way I've found to stop it from disabling that feature is to not move the window when the program is open.
You may have a similar situation, open your installed programs one at a time and see which one does not show contents while dragging, then you'll know which one not to move when open and once you found the program, you'll have to go back and re-enable that function as first described.