My Dell 2200Mp is a little over 2 years. I recently started to get a dark bar that appeared diagonal across the upper right of the screen. I figured it was the bulb. I paid for a new bulb-ouch!

I've replaced the bulb. Now, the dark spot has gotten worse. It is more geometric. It has right angles and covers 3/4 of the viewing area. Some times, if I tap on the projector, the shadow moves. I have looked at everything-minus fully taking the projector apart.

I do not wish to take the projector apart. But, I have  removed some parts in order to blow compressed air into the projector. I've dusted this entire machine. Although it needed dusting, that didn't solve the problem. Is there something else I need to do? I have replaced the bulb, by following the online directions. I have cleaned the lens that is accessible beneath the bulb. What else?