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 the VGA Display dialog box, click the Arrange tab, and make sure Mirror Displays is checked.
click here
select Mirror Displays
24Using the Projector