Microsoft Outage Impacts Users in Canada and the U.S.

Microsoft suffered a widespread outage on Thursday afternoon that impacted tens of thousands of users across Canada and the U.S., with reports spiking on Downdetector as services like Outlook, Teams, and Copilot failed.

ET. The disruption began shortly before 1 p.m. ET, according to [CNBC], with nearly 150,000 users reporting issues accessing Microsoft Outlook in both countries at its peak. By 9:30 p.m. ET, more than 35,000 combined reports remained active, while Canada experienced a late spike of nearly 6,700 reports, [CTV News] reported. Microsoft’s service incidents social media account said it was investigating. “While we’re working to mitigate impact, we’ve confirmed the issue may affect Microsoft 365 service connectivity for users in any region, more information will be provided in the Microsoft 365 admin center under EX1550543,” the account said.

The company later added: “We’ve determined a portion of infrastructure is experiencing elevated load across multiple regions, which is likely contributing to the connectivity errors,” according to [Global News].

Subsequent investigations by Microsoft revealed the elevated load stemmed from a number of servers becoming “unexpectedly unavailable” after failing automated health checks, which strained the remaining network infrastructure. The peace and quiet is nice LOL,” wrote one user. “Please leave Outlook down till Friday 5 pm :),” wrote another.

Hospitals and Transit Affected

Unity Health Toronto declared a “Code Grey,” an administrative designation used during infrastructure failures, after staff experienced difficulties sending and receiving emails across its network. “Please be advised that patient and resident care is not affected by the outage,” Unity Health said, according to Unity Health Toronto. “Our hospitals remain safe and open to provide care.” Staff were instructed: “If you are staff member, please use alternative communication for important information or use our internal website UnityNet.”

Rail transport also felt the pinch.

VIA Rail Canada announced on social media that passengers might not receive email confirmations or trip updates due to the severed connectivity. “We encourage passengers to use the VIA Rail train tracker or to subscribe to SMS notifications through the Via Rail Train Status & Schedules Page to get the most updated information about their train,” the company said.

Several post-secondary institutions, including the University of Toronto, Seneca Polytechnic, and George Brown Polytechnic, also reported disruptions to their email systems without classes being canceled.

Outage Reports Hit 74 Countries During Microsoft Exchange Disruption

Downdetector recorded outage reports across 74 countries and territories within roughly an hour on Thursday, while separate glitches simultaneously touched Amazon Web Services and Google’s Gmail. Microsoft reported that its Exchange Online incident officially began at 16:17 UTC. Amazon wrote on X that services were “operating normally” and an “unrelated disruption elsewhere on the internet is prompting some inaccurate news reports.” The company referred users to its health dashboard for “accurate data.” At 4 p.m., Microsoft said it had “validated an alternative service health check method” that brought some affected servers back online.

“We’re now applying this change more broadly,” Microsoft wrote. “We’ve monitored the status of the changes applied to improve serviceability and confirmed that change is not taking as expected,” Microsoft said on its website. The company added that it was identifying “alternate workstreams” to increase capacity against sustained traffic management imbalances.

Microsoft said it had not identified any “recent change correlated with the start of the impact.” “However, our investigation indicates the failed health checks may originate from a specific component that’s responsible for processing server health,” it said.

More on this story: Microsoft Outage Disrupts Outlook, Teams, and Microsoft 365 Services Globally

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