If you ever used a second monitor / screen with your laptop,and you disconnected it without moving the windows back to your current desktop,you may faced that the application were running but you can not saw the window in current screen,although you can saw it on your taskbar.If so please follow below steps to get your off-screen window back to your desktop.
Click or use Alt+Tab to active this window,then right-click your taskbar and click Cascade Windows
If you are using windows 7,just press key WIN+Left Arrow or WIN+Right Arrow to get your off-screen window back to your current screen
Right-click(For windows 7,use Shift+Right-click) the window icon on your taskbar and select Move,then press one of your Arrow keys ,then move your mouse,then your off-screen window should go back to your current desktop
Note:If the window was maxmized,please Right-click (Shift Right-click) ,select Restore ,then repeat
Similiar as method 3,use Alt+Tab the active this window,then press Alt+Space,then press M ,then press one of your Arrow key to get your off-sceen window back