xbox 360 messing up and halo wars demo

Hey my xbox 360 is screwing up. I posted a message similar to this a month or two ago but it's more extreme. I was told my "lens" was dirty. I figured i needed a lens cleaner and got one at Wal-Mart and cleaned the lens. When my xbox didn't recognize it this time I figured to do the same thing. But this time it can't recognize the lens cleaner either. I can play demos, watch videos, and do anything else on the dashboard exept play games. So I'm wondering what I should do about it this time. Also I realize that a lot of other people have the Halo Wars demo already. I started the download at approximately 7:10 A.M. and checked on it at about 3:10 P.M. and it hasen't downloaded at all, I mean like 0% complete. My xbox was off also if that has much to do with it. Does anyone know why that is?

While I don't know about the lense problem, if you shut off your 360, the demo won't download.Legendaryscmt

You can turn on an option to download things in your download que while your system is turned off. When they're done downloading the system will shut itself off.

Go to your system settings>Shutdown>Enable background download.

360 CAN download stuff while off, as long as the system settings are enabled. specifically, the one that enables a download while the system is off __ _ __ ______ __ _ __ _ _ GranmastaZoSo

Exactly, your 360 just keeps the components it needs on while it downloads. You will see the power button blink every now and then and that's how you know it's still downloading something. You just have to have the right setting enabled like these guys said.

THANKS!!!!!!!!!!!!!!!!!!!!!!!!!!!

Someone might say even 360 is off the download will keep going... and that's not true.SiKyung

can background download cause red ring of death?