Ok, so I downloaded the Empire at War demo, I checked it was the right size, in case there was an error. So I install it, and thats all fine, but when I actually try to start the game I get an error:
1024MB DDR400 RAM
GeForce 6600GT (With the latest 81.98 Forceware Drivers + DirectX 9.0c)
80GB SATA HDD
I have no idea what could be the problem!