Connecting to projector

Question

Is there another way to connect the acer aspire to a projector? The fn+F5 does not do it . I was able to connect before but not anymore. Is there something I did to the start up programs or to the settings that caused this to no longer send the screen to the projector? Ugh! Please help I am a teacher and use my computer all the time to project info on my board. Thank you:-)