This procedure applies when two or more monitors are connected to one computer.
Open Display in Control Panel.
On the Settings tab, click Identify to display a large number on each of your monitors, showing which monitor corresponds with each icon.
Click the monitor icons and drag them to positions that represent how you want to move items from one monitor to another, and then click OK or Apply to view changes.
To open Display, click Start, click Control Panel, click Appearance and Themes, and then click Display.
The icon positions determine how you move items from one monitor to another. For example, if you are using two monitors and you want to move items from one monitor to the other by dragging left and right, place the icons side by side. To move items between monitors by dragging up and down, place the icons one above the other. The icon positions do not have to correspond to the physical positions of the monitors. You can place the icons one above the other even though your monitors are side by side.