First of all, look on the projector and find the model number - that will really help. Then check your display settings (right click on desktop and choose properties). Click the settings tab, then click advanced. You should have some way to adjust your display device (LCD only, LCD+CRT, CRT only). Some notebooks do not automatically send a signal to the VGA connector. You should have a key to toggle the display output. On my toshiba laptop, I have to press Fn (Function) + F5. Also, like Microbell said, you might have to adjust your resolution to a lower setting - older projectors will not do that automatically like the newer ones will. Let me know if you need any more help - I use my LCD projector on a regular basis.
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