I wondered whether someone could help. My dell 1545 laptop is refusing to start up, saying windows 7 has a problem, the screen is blank. Have tried everything booting up in different modes. It has happened before and the laptop seemed to just retify it on it's own. The only other problem with it at the moment is the battery is dead so am using the mains to power the computer - have ordered a new battery. It runs on 64 bit OS.