If you’re using a Macintosh laptop with OS X:
You may need to set up your system to display on the projector screen as well as the LCD screen. Follow these steps:
1.From the Apple menu, select System Preferences, then click
Displays.
2.Select VGA Display or Color LCD, click Arrange or Arrangement, and make sure Mirror Displays is checked.
Click here
Select Mirror
Displays
24Using the Projector