 Good evening, I'm Maurice Dubois in for Norah O'Donnell. It is being called the largest IT outage in history, and it could affect your flight, your surgery, your deliveries, even your paycheck, and the cause of faulty software update. Millions of workers were met with a blue screen of death when they turned on their computers today. Airports across the country and around the world were packed with stranded passengers. Planes were grounded by the thousands, not by the weather, but by this technical tsunami.