Thousands of workers face disruption on Friday as Microsoft struggles to restore its services following a global outage that has knocked out Outlook, Teams and its AI assistant Copilot for more than 14 hours.
Microsoft said its attempts to fix the problem had produced only partial results, warning that services could become unresponsive again even after being restored.
“We’re continuing to work on recovering our frontend servers while implementing further traffic optimisation actions to improve service stability and increase capacity,” the company said. “We’re aggressively pursuing all pathways to reduce impact”.
Reports of problems accessing Outlook peaked at nearly 140,000 globally around 6pm GMT on Thursday, according to monitoring website Downdetector.
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SUBSCRIBE HEREMicrosoft attributed the disruption to servers becoming unexpectedly unavailable, placing additional strain on its remaining infrastructure. It ruled out a cyber attack.
Microsoft outage exposes reliance on US tech
The disruption threatens to derail the working day for British businesses heavily reliant on Microsoft’s software for emails, meetings and internal communications.
Swiss luxury goods group Richemont was also forced to delay the announcement of its half-year financial results on Friday morning due to the outage, although it subsequently published the figures.
More than 430m people worldwide use Microsoft 365 applications, while AI giants OpenAI and Anthropic have also reported problems with services connected to Microsoft’s infrastructure.
Technology analyst Paul Spain warned the disruption could become the “most severe technology outage in history” if it continued for 24 hours, potentially affecting billions of dollars in business operations.
The outage has already disrupted banks, government agencies and courts across several countries, with some organisations forced to delay operations.
It also comes as European governments seek to reduce their dependence on American technology providers and strengthen domestic digital infrastructure.
Toby Murray, a computing professor at the University of Melbourne, warned of the “inherent dangers” of such dependence, saying a major outage at one provider could “dramatically reduce business productivity globally”.
The incident follows a separate outage at Microsoft’s Azure cloud platform last month and echoes the global IT failure in 2024, when a faulty CrowdStrike update grounded flights and disrupted banking services.
It also comes at a bruising time for the US tech sector, after Nvidia shed nearly $600bn in market value on Thursday following the resignation of its long-serving chief executive Jensen Huang.
The chip giant’s collapse added to a wider tech sell-off, with investors already questioning whether the billions being poured into artificial intelligence will deliver sufficient returns.