Windows 10 – Duplicate or Extend Your Screen
If you’ve got a second screen connected to your Windows computer, either an interactive screen, projector or a screen by the side, Windows makes it easy to change your second screen or projector display mode. To switch between display modes simply press Windows + P.
– PC screen only uses your current display.
– Duplicate shows the same content on both displays (monitors/interactive screens/projectors).
– Extend splits the image between the two displays. This is useful for displaying your presentation on the interactive screen/projector while displaying your speaking notes on the PC/laptop.
– Show second screen only turns off the current display and displays the desktop only on the interactive screen/projector.
If you can’t see anything on the interactive screen/projector make sure the display mode is set to Duplicate Desktop. The new setting should take effect straight away.
If all else fails, try unplugging the HDMI/VGA cable and plugging it back in again.