Microsoft’s Outlook, Teams, and Copilot services were slowly recovering on Friday after an outage that lasted at least 12 hours, disrupting government and business communication systems worldwide.
The Redmond, Washington-based tech giant blamed server problems for the outage and denied it had been the victim of a cyberattack.
“We’re continuing to see improvements in service availability, with email queues significantly reduced and approaching normal levels,” Microsoft said in an update at 9 a.m. ET.
“Some users may still experience intermittent access issues or delayed email delivery as recovery continues.”
“At this time, we have no evidence of malicious activity associated with this incident,” Microsoft said on its website.
“We will continue to treat this with urgency until full mitigation, and we will share a full Post-Incident Report with root cause and defense-in-depth actions after mitigation is complete.”
It said a wide range of Microsoft 365 offerings that interact with its Exchange Online and email services were affected. More than 430 million people worldwide use Microsoft 365 apps, the company said.
The outage disrupted government agencies in the United States, Australia, and Japan, and delayed many companies from publishing results to stock exchanges.
Airlines also warned customers of possible impact to passengers.
A series of posts by Microsoft 365 Status, the company’s official service incident account, on X on Thursday evening suggested its engineers were running into setbacks as they worked to apply fixes.
“The servers we returned to service can become unresponsive again once they receive traffic; we’re analyzing diagnostic data to determine what’s triggering the behavior,” Microsoft 365 posted at one point.
“We’ve monitored the status of the changes applied to improve serviceability and confirmed they’re not taking as expected,” Microsoft 365 Status wrote on X later.
“We’re identifying alternate workstreams that can be applied to increase capacity in the face of sustained traffic management imbalances.”
Microsoft said on Friday that it was seeing signs of stabilization after implementing fixes to restore service to customers.
Situation ‘Improving’ in North America
“We’re seeing encouraging recovery progress in Europe, with service availability and email delivery performance improving across a growing portion of affected Microsoft 365 infrastructure,” the company added.
“Japan remains comparatively more stable, while North America is also improving; however, some users may still experience intermittent issues as recovery actions continue.
“We’re focused on addressing the remaining areas of disruption and improving service consistency across affected regions.
“Reducing email queues and backlogs remains a priority, and the extended 48-hour email timeout window remains in place to help protect delayed messages as delivery catches up.”
Australia’s home affairs minister, Tony Burke, who also oversees cybersecurity, said Microsoft likened the outage to the CrowdStrike incident in 2024.
An antivirus software update issued July 18–19, 2024, by CrowdStrike, one of the largest cybersecurity companies, caused more than 8.5 million Windows-based devices to crash, disrupting essential operations at airports, hospitals, 911 centers, police departments, trains, jails, municipal services, and corporate operations.
“[Microsoft] don’t believe they are dealing with a cyberattack,” Burke said. “They believe that they are dealing in some ways, similar to what we saw with respect to CrowdStrike where there is an update that has gone awry.”
Japanese deputy chief cabinet secretary Masanao Ozaki said the government in Tokyo was “keeping a close eye on the developments,” but accepted the outage had impacted the government’s IT infrastructure.
U.S. President Donald Trump and Secretary of Homeland Security Markwayne Mullin have not yet commented on the outage.
Britain’s National Cyber Security Centre (NCSC) issued a warning in a post on X on Friday, as a result of the outage.
“In the wake of the global Microsoft outage, the NCSC is recommending that everyone exercise caution around unexpected calls and messages, especially those containing links,” it said.
The Associated Press and Reuters contributed to this report.
