Global business operations came to a standstill on Friday morning due to a glitch at a cybersecurity software provider that grounded airplanes and disrupted financial institutions.

The outage was caused by a software update at cybersecurity firm Crowdstrike, crashing computers running Microsoft's Windows operating system. Airports, airline carriers, banks, media companies, health care providers, railway operators and the London Stock Exchange saw operations grinding to a halt.

The incident demonstrated the fragile dependence of the global economy on digital service providers. It is expected to trigger a massive fallout in compensation claims and IT cleanup operations that some observers are calling unprecedented.

“It is hard to estimate how long recovery will take,” said Ciaran Martin, professor of practice in the Management of Public Organisations at the Blavatnik School of Government. “Some industries can recovery quickly. But others like aviation will have long backlogs.”

Users took to social media as of Friday morning to report “blue screens of death,” a sign of malfunctioning Windows laptops or workstations.

Melbourne airport was among those affected, citing a "global technology issue" that disturbed “check-in procedures for some airlines,” it said on X.

Airports across Europe also struggled. Dutch airport Schiphol said a “global computer failure” had impacted flights. London Gatwick noted problems in check-in procedures, citing “global Microsoft issues.” Berlin Brandenburg airport also reported delays at check-in.

Ryanair warned on its site that due to a “global third party IT outage,” booking and check-in were unavailable.

Other transport companies, such as the Belgian railway company, cited IT issues impacting sales channels or online announcements.

The London Stock Exchange operated normally but said it could not publish news on its site.

Major broadcasters also reported issues preventing them from broadcasting live. Several Sky employees flagged issues on X.

A No. 10 spokesperson said officials had held a COBR emergency meeting — the U.K.'s dedicated channel for responding to civil emergencies normally attended by senior ministers — to discuss the outage.

The European Commission's spokesperson service said: "We are aware of the media reports on the cyber incidents that have affected various sectors in EU member states and worldwide." It added that its own services were not affected.

Microsoft acknowledged that it experienced two nonrelated issues: one on its cloud platform Azure, and another related to cybersecurity firm CrowdStrike.

“We are aware of [an] issue affecting a subset of customers,” it said in a statement shared with POLITICO on Azure. Separately, it also said to be “aware of an issue affecting Windows devices” due to a CrowdStrike update. “We anticipate a resolution is forthcoming.”

CrowdStrike said in a statement it was “actively working with customers impacted by a defect found in a single content update for Windows hosts. Mac and Linux hosts are not impacted.”

“This is not a security incident or cyberattack," the cybersecurity firm said. “The issue has been identified, isolated and a fix has been deployed ... We further recommend organizations ensure they’re communicating with CrowdStrike representatives through official channels.”

Russia's Digital Communications Ministry noted that it had not been affected by the global tech outage.

“The situation with Microsoft once again demonstrates the importance of import substitution of foreign software,” said the ministry in a press release, hinting that sanctions against Russia following its full-scale invasion of Ukraine in 2022 helped in avoiding the current tech disruptions.

This story has been updated.

Ketrin Jochecová contributed reporting.