Hi! I've been trying to install Windows 7 for like 3-4 times now and every time I get to the Completing Installation part I wait a little and suddenly I get a red error box and it says something about "Windows cannot be installed..." and then pc shuts down. The error box is there for like 0.5 seconds so I cant read it, but its just like 1 sentence. "Cannot be installed" and something after that. What do I do ?