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. CrowdStrike is 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 are now spreading, as businesses based in Europe are starting their working days. UK broadcaster Sky News is currently unable to broadcast its morning news bulletins, and is 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.

The US Federal Aviation Administration says all flights from Delta, United, and American Airlines are grounded due to a “communication issue.” Berlin airport is also warning of travel delays due to “technical issues.” Many 911 emergency call centers in Alaska have also been impacted by the issues.

“We have widespread reports of BSODs on Windows hosts, occurring on multiple sensor versions,” says CrowdStrike in a support note issued at 1:20AM ET today. CrowdStrike has identified the issue and reverted the faulty update, but that doesn’t appear to help machines that have already been impacted.

In a Reddit thread, hundreds of IT admins are reporting widespread issues and the workaround steps involve booting affected Windows machines into safe mode and navigating to the CrowdStrike directory and deleting a system file. That will be troublesome on some cloud-based servers, or even for Windows laptops that are deployed and used remotely.

“Our entire company is offline” says one Reddit poster, while another says 70 percent of their laptops are down and stuck in a boot loop. “Happy Friday,” says one Reddit poster. It looks like it’s going to be a long day for IT admins worldwide.

In what appears to be a separate outage, Microsoft is also recovering from several issues with its Microsoft 365 apps and services. The root cause of those issues was down to “a configuration change in a portion of our Azure backend workloads.”