Thousands of Windows machines are experiencing a Blue Screen of Death (BSOD) issue at boot today, impacting banks, airlines, TV broadcasters, supermarkets, and many more businesses worldwide. A faulty update from cybersecurity provider CrowdStrike is knocking affected PCs and servers offline, forcing them into a recovery boot loop so machines can’t start properly. The issue is not being caused by Microsoft but by third-party CrowdStrike software that’s widely used by many businesses worldwide for managing the security of Windows PCs and servers.

Australian banks, airlines, and TV broadcasters first raised the alarm as thousands of machines started to go offline. The issues spread fast as businesses based in Europe started their workday. UK broadcaster Sky News was unable to broadcast its morning news bulletins for hours this morning and was showing a message apologizing for “the interruption to this broadcast.” Ryanair, one of the biggest airlines in Europe, also says it’s experiencing a “third-party” IT issue, which is impacting flight departures.