Cannot connecting projector with notebook but can with desktop pc

hi expert, i've got a problem with connecting notebooks with projector. therefor i was ok, but now then it's wont work. i have try to change the resolution setting, but still did not appear on the whiteboard screen. there were only a startup windows appears on the screen board, but after we log its doesnt show any images. there's something make me curious, when im connet the projector with desktop pc, there is no any problem...??? could you please help me?