Microsoft restored its flagship software services after a major outage disrupted businesses across more than 70 countries. The company said, "We are deeply sorry for the disruption this incident has caused our customers and partners." A network capacity upgrade caused the technical failure, which affected Outlook, Teams, and Copilot.
Microsoft has restored access to its flagship software services after a major outage disrupted businesses, government offices and critical services across more than 70 countries, forcing users to find alternatives to email, online meetings and other digital tools.
The company said all products were operational and that the backlog of email messages had been processed, bringing the disruption to an end. Services affected included Outlook, Teams and its Copilot artificial intelligence assistant.
"We are deeply sorry for the disruption this incident has caused our customers and partners," Microsoft said in a post on X, adding that it takes the responsibility associated with customers' trust in its services seriously.
Quick answers to key questions
Microsoft said the disruption followed a network change after a network capacity upgrade. The issue affected Exchange servers, which became unresponsive as they rapidly used their available resources.
Outlook, Teams, Copilot, Exchange Online, SharePoint and other Microsoft 365 services were affected. Microsoft says all products are operational and the backlog of email messages has been processed.
No. Microsoft said the incident was technical in nature and not related to a cyberattack or artificial intelligence.
The disruption prevented users from accessing email, meeting invitations and workplace communication tools. Some organisations reported delays to communications and transactions, while others used alternatives such as phone calls or fax.
Microsoft addressed the underlying technical issue and restored services to affected customers and regions in stages, checking stability as it went. The company said it will publish a detailed post-incident report after its review.
The company said it had addressed the underlying technical issue and restored services to the remaining affected customers and regions. It added that it would publish a detailed post-incident report after completing its review.
What exactly happened?
According to Bloomberg, the disruption was triggered by an issue during a network capacity upgrade. Microsoft said the problem surfaced following a subsequent network change.
The failure affected Exchange, the service that powers email and calendars across Microsoft's 365 productivity suite. Bloomberg reported that Exchange would start up on a server but rapidly consume its available resources, eventually becoming unresponsive.
The resulting disruption affected other services and left users unable to access emails, invitations and web pages. Microsoft said the incident was technical in nature and was not related to a cyberattack or artificial intelligence and agents.
The company also said its recovery efforts were carried out gradually. Given the scale of demand, it restored services in stages while checking their stability at each step.
According to Bloomberg, more than 1,000 Microsoft engineers and employees were involved in the response, with sessions led by cloud chief Scott Guthrie and Charles Lamanna, who oversees the Microsoft 365 bundle and other workplace applications.
The outage began showing up in user reports at around 1 pm on Thursday on the US East Coast. Downdetector recorded hundreds of thousands of complaints, with users in more than 70 countries reporting problems.