CrowdStrike global Windows crash latest updates — aftermath of the biggest IT outage in history
Windows machines around the world experienced a significant IT issue

The devastating IT issue caused by a faulty update pushed to Windows PCs by cyber security company CrowdStrike is continuing to weak havoc days later. The problem first came to global attention early Friday morning, knocking companies and banks offline and grounding planes at various airports. While the initial bug was identified and fixed that same day, the knock-on effects are continuing.
CrowdStrike is used by businesses worldwide, including banks and airports, and the fault occurred due to an update error involving its Falcon Sensor software. When deployed automatically to millions of PCs around the world, it inadvertently put them into a recovery boot loop. The resulting Blue Screen of Death (BSOD) began to appear worldwide and knocked countless systems offline.
While CrowdStrike implemented a fix to the fault, this will only stopped more machines from crashing. It couldn't help those already affected which, according to Microsoft, was about 8.5 million devices worldwide.
Now the cleanup operation is in full swing as businesses look to recover their lost systems and airlines try to get customers to their final destinations.
Our live blog below shows the updates as they happened through Friday (July 19) and into the aftermath of what's being called the biggest IT outage in history.
Global Windows IT issue: What we know
A substantial global IT issue knocked Windows PCs offline for banks, broadcasters, airlines, health clinics and more.
- Australian companies first reported the error after broadcasters and banks could not load their Windows machines. Greeted by the Blue Screen of Death (BSOD), the devices failed to boot properly, knocking them offline.
- As Europe began to start the work day, it became clear this was a widespread global issue affecting multiple industries. Across the world, flights were grounded due to the error. In the U.K., broadcaster Sky News was unable to broadcast its news bulletin, and clinics were unable to book patient appointments.
- A faulty update caused the issue pushed through from cybersecurity firm CrowdStrike, which meant affected devices could not load correctly.
- At 1:20am ET on Friday, July 19, CrowdStrike issued a support note saying it had identified and reverted the issue. However, this only prevents more machines from hitting the BSOD and can't recover those already affected.
- Microsoft, one of the largest affected companies, appeared to have suffered a separate outage that mainly affected Microsoft 365 apps and services due to a configuration change in its backend Azure settings. The company says it has now fixed these.
- CrowdStrike CEO George Kurtz posted to X at 5:45am ET/10:45am BST that the issue was caused by a "single update for Windows hosts" and that the "issue has been identified, isolated and a fix has been deployed." However, the knock-on effects are continuing to cause mass disruption.
- Microsoft's Satya Nadella commented on the issue stating that Microsoft is aware of the situation. "We are aware of this issue and are working closely with CrowdStrike," reads his X post.
- CrowdStrike posted a technical breakdown of what happened. It's a lot of information, but if you want to know more than "it was a software update," it's worth reading.
- Airlines are trying to recover, but passengers are reporting long wait times at airports to get on their flights.
- Thousands of flights were canceled on Saturday worldwide, and more than 1,000 flights have been canceled as of 8:30am ET.
- As of Monday, July 22, Microsoft estimates that as many as 8.5 million Windows PCs were affected by the faulty update.
What is CrowdStrike?
CrowdStrike is a global cybersecurity company that proudly declares in its X profile, "We Stop Breaches." It offers threat intelligence and protection from cyber attacks to a range of large companies, including Microsoft and many large airlines.
Founded in 2011, the publicly traded company has also led several high-profile investigations into cyber espionage attacks, including against Sony Pictures and the Democratic National Committee.
It produces security software for Windows servers and machines that are designed to detect and prevent attacks, including its Falcon Endpoint and identity protection platform.
This comprises various modules, including ones that track system vulnerabilities and others that sandbox malware. Falcon is also widely used on public sector infrastructure and in data centers such as those powering Microsoft Azure and Microsoft 365 services.
Falcon Sensor is one of the modules in the Falcon platform designed to prevent cyber attacks, and an update to this module triggered the global outage.
Microsoft working to fix "Service Degradation"
Despite the chaos unfolding across the world, Microsoft is working quickly to fix the "service degradation" it notes on its cloud status page. An update at the top of the page reads: "Users may notice that some of the affected users are seeing relief as we continue to mitigate the impact."
According to Microsoft, the following services should be working normally.
- Microsoft Defender
- Microsoft Defender for Endpoint
- Microsoft Defender Experts
- Microsoft Intune
- Microsoft OneNote
- OneDrive for Business
- SharePoint Online
- Windows 365
- Viva Engage
- Microsoft Purview
CrowdStrike update takes out large parts of the web
Updates from cybersecurity company Crowdstrike are the most likely cause of the global IT outage that has taken parts of Microsoft Azure and 365 offline, leaving individuals and companies unable to offer services.
We’ve seen hits to the NHS in the U.K., TV news stations including some Fox affiliates and Sky News in the U.K. and Australia taken off air and banks unable to provide services. There have also been transport issues with flights unable to take off and trains facing delays.
Microsoft says it has applied fixes to Azure and other platforms and things are starting to return to normal, but says some users will experience disruption throughout the day.
Flights grounded due to CrowdStrike fault
The Federal Aviation Administration says all flights from United, American Airlines and Delta have been grounded due to a "communication issue" which Delta and United have confirmed is linked to the global outage.
A United spokesperson said in a statement: "While we work to restore those systems, we are holding all aircraft at their departure airports. Flights already airborne are continuing to their destinations."
The Microsoft / CrowdStrike outage has taken down most airports in India. I got my first hand-written boarding pass today 😅 pic.twitter.com/xsdnq1PgjrJuly 19, 2024
Berlin Airport in Germany is warning of major delays and RyanAir, Europe's largest airline, says a global third-party IT outage has caused disruption across the entire network. Delhi Airport in India has gone completely manual, writing out baggage tags and boarding passes.
CrowdStrike has a fix for Blue Screen of Death
Here is the solution for the @CrowdStrike Issue guy !!#csagent #bsod #crowdstrike #windowsissues #Windowsdown pic.twitter.com/XmajoqQpFlJuly 19, 2024
On the consumer side of things, Windows computers were being served a blue screen of death due to a global CrowdStrike issue. These crashes were due to a “Falcon Sensor” issue — ironically this is the software that’s supposed to defend computer systems from crashing due to cyber attacks.
In the past hour, Crowdstrike came out with a resolution if you’re still seeing this issue.
That should fix it, but if you’re still seeing issues, pipe up in the comments! Now for the world’s businesses…
911 emergency response affected in the United States
The list of companies being impacted is largely just a bunch of annoying inconveniences, such as Xbox Live being down for a bit (it’s back up) and Microsoft 365.
But there are some real scary consequences of this too. Namely, 911 emergency response is being hit hard across the US. According to Down Detector, we’re seeing big dropouts in the following states:
- New York
- Washington
- Atlanta
- Florida
- Texas
- Arizona
- California
- Missouri
- Michigan
- Illinois
Fortunately, this outage seems to be on the decline, as the number of people reporting has declined. But we’ll keep a close eye on this.
U.K. health service impacted by outage
People in the U.K. are seeing their national health service (NHS), unable to take appointments due to problems with their systems as a result of the faulty update.
So far, we're seeing clinics in Yorkshire, Cheshire the West Midlands and Chorley unable to take any appointments. The NHS has been affected by systems crashes before and, along with the immediate impact, there's often a backlog that can be caused in the aftermath.
An NHS spokesperson said: “The NHS is aware of a global IT outage and an issue with EMIS, an appointment and patient record system, which is causing disruption in the majority of GP practices.
“The NHS has long standing measures in place to manage the disruption, including using paper patient records and handwritten prescriptions, and the usual phone systems to contact your GP. Ther