Massive Microsoft Windows Outage Bricks PCs, Halts Flights Worldwide (2024)

Microsoft systems and Windows PCs around the world experienced a sudden outage early Friday morning when cybersecurity firm CrowdStrike released an update, causing computers to become stuck in the "blue screen of death" (BSoD).

Users reported issues with Microsoft, its store, and Microsoft 365 services beginning around 6:30 p.m. ET Thursday night, according to Downdetector.com data. Around 7:40 p.m. ET, Microsoft reported that its services were experiencing disruptions. The tech firm released hourly updates noting that it was rerouting traffic to working infrastructure and said that the issue continued to "see improvements" by 4 a.m. ET.

Microsoft's status page explains that its Azure cloud service was impacted. "We have been made aware of an issue impacting Virtual Machines running Windows Client and Windows Server, running the CrowdStrike Falcon agent, which may encounter a bug check (BSoD) and get stuck in a restarting state," the page states.

Some airlines were unable to operate as a result of the Windows issues, with reports that Southwest, Frontier, American Airlines, Delta, and United Airlines had inoperable computer systems and grounded flights due to the resulting communication issues. The BBC reports that approximately 1,400 flights have been cancelled as a result of the outage.

"The FAA is closely monitoring a technical issue impacting IT systems at US airlines. Several airlines have requested FAA assistance with ground stops until the issue is resolved," the US Federal Aviation Administration said on X early Friday morning.

CrowdStrike has since retracted the update that bricked machines around the world. "We can confirm the affected update has been pulled by CrowdStrike," Microsoft notes. "Customers that are continuing to experience issues should reach out to CrowdStrike for additional assistance. Additionally, we're continuing to investigate additional mitigation options for customers and will share more information as it becomes known."

CrowdStrike CEO George Kurtz wrote on X around 5:45 a.m. ET that the company is working to fully resolve the issue and confirmed that no Mac or Linux systems were impacted. "CrowdStrike is actively working with customers impacted by a defect found in a single content update for Windows hosts," Kurtz said, adding: "This is not a security incident or cyberattack. The issue has been identified, isolated and a fix has been deployed."

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But Azure also caused issues with Microsoft 365, impacting a dozen different Microsoft services like Microsoft Defender, OneNote, One Drive, and Teams. Microsoft shared that the issues with Defender, OneNote, and OneDrive have been resolved, while issues with Teams may persist for some users.

"A configuration change in a portion of our Azure backend workloads caused interruption between storage and compute resources which resulted in connectivity failures that affected downstream Microsoft 365 services dependent on these connections," Microsoft said.

But CovertSwarm IT Infrastructure Manager Tony Law believes the Microsoft 365 outage may have been a "self-inflicted" wound separate from the CrowdStrike update incident.

"It seems to be self-inflicted," Law tells PCMag via email. "The unconnected CrowdStrike issue was seemingly simply buggy code that wasn't QA'd sufficiently."

While CrowdStrike has already pulled its problematic update, some Windows PC users may continue to encounter issues. At approximately 6:45 a.m. ET Friday, Microsoft noted that Windows 365 Cloud PCs are impacted by the CrowdStrike issue, and suggests users restore their machines to a "known good state prior to the release of the update."

Law says businesses should thoroughly test any software changes and automatic updates "within pre-production environments prior to any push to production" to avoid being impacted by a similar type of outage in the future.

PCMag has reached out to CrowdStrike and Microsoft for comment.

In a late-morning tweet, Microsoft CEO Satya Nadella said: "Yesterday, CrowdStrike released an update that began impacting IT systems globally. We are aware of this issue and are working closely with CrowdStrike and across the industry to provide customers technical guidance and support to safely bring their systems back online."

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