it is a massive computer outage affecting all corners of the globe which could well be the biggest outage the world has seen not a Cyber attack but a software update gone bad affecting Microsoft Windows computers using crowd strike cyber security software Crow strike is aware of reports of crashes on Windows hor among the first affected Global Airlines their screens suddenly showing the so-called blue screen of death from Thailand to Portugal Spain to Scotland and I think it's fair to describe this as organized chaos at the moment US Airlines went offline overnight unable to process thousands of passengers every 15 minutes we kept getting these text messages your flight is delayed a half hour your flight is delayed an hour your flight is delayed 2 hours major airlines grounded flights with Flight Radar 24 showing us airspace thinning out as endless lines wound through airport terminals we received no uh no you can't get through to the to the uh to the airline I don't think it's even in their hands NBC's guad Vegas in Atlanta passengers here reporting weights of up to 4 hours waiting on a line that stretch to the end of the terminal by late today 9500 delays in the US 2700 cancellations akin to the impact from a big winter storm we're deeply sorry for the impact that we've caused to customers the CEO of crowd strike which pushed the software update appeared on today so um we know what the issue is uh we're resolving and have resolved the issue but it wasn't just Airlines and airports hospitals were also knocked offline nurses switching to paper orders we can't scan the medicine to make sure you're not allergic to it we can't scan the medicine to make sure that it's even yours many hospitals forced to cancel procedures Alison balo's father was supposed to have open heart surgery they called and said that due to a global it outage they had to reschedule the surgery also affected Banks 911 systems trains buses and Subways retailers FedEx and UPS court systems and driver's license offices New York's Governor trying to reassure the public there is no risk to personal sensitive information that we're aware of on x Microsoft said it's working closely with crowd strike and across the industry to safely bring their systems back online uh doesn't this speak to a vulnerability that you have with Microsoft Windows that one line of code could break down the entire system there is no vulnerability based on our knowledge what we understand right now is that the crowd strike update itself was flawed in how they accessed the system and that is what has caused the global it outage all right Tom joining us now Tom how long is this outage expected to last well the airlines seem to be back mostly back back uh but the ripple effect from the flight cancellations could run well into the night likely through the weekend and it could take hospitals shipping companies retailers days or weeks to fully recover Lester thanks for watching stay updated about breaking news and top stories on the NBC News app or follow us on social media