Sometimes, Windows will display the program off-screen, which can occur most often when switching display output (e.g. additional external monitor) which makes it appear as if the program isn’t opening, or not displaying at all. There are a two options to correct this:
Option 1: Hold CTRL and Shift, then Right-Click on the program Icon on your Windows Taskbar. Select Move from the options listed and you’ll be able to use your arrow keys to move the program into view.
Option 2: Right-click on the Windows Taskbar and select Cascade Windows. All programs you have open will show stacked and you can select the one of interest.