Microsoft services became operational again on Saturday after a global outage disrupted Outlook email and other Microsoft 365 workplace services, affecting email-based customer support at Indian airlines and operations at financial services firms.
Microsoft’s service health page displayed “All products are operational” on Saturday morning, including Microsoft 365 business and enterprise services as well as consumer products. The company said it was “deeply sorry” for the disruption and attributed the incident to a technical issue connected to an earlier network capacity upgrade.
The company said the problem surfaced after a recent network change and was not related to cyber activity, artificial intelligence or AI agents. Microsoft said it had addressed the underlying issue and restored services gradually, checking stability at each stage because of the scale of demand.
The outage began late on Thursday and primarily affected Microsoft 365 features that interact with Exchange Online, Microsoft’s cloud-based email platform. Users reported difficulty accessing mailboxes through Outlook on the web and desktop applications, while email delivery was delayed.
Indian airlines IndiGo, Air India and Akasa Air reported disruptions to email-based customer support. The problems affected the airlines’ ability to receive or respond to some passenger queries, although flight operations were not reported to have been affected. Air India temporarily rerouted its email services to keep customer communications moving.
The disruption also affected financial services firms, which reported difficulties accessing research reports and conducting client interactions. These effects highlighted how routine customer service, business communication and operational coordination now depend on cloud-based workplace systems rather than locally managed email infrastructure.
At its peak, the outage generated more than 1.3 lakh reports of Outlook problems on outage-tracking website Downdetector. Disruptions were reported across 72 to 74 countries, according to the PTI report.
Microsoft said the restoration took longer because services were brought back in stages. The company’s status account on X said it was continuing to monitor recovery because of the severity of the incident and was watching the backlog of emails created during the outage to ensure they were processed before declaring the issue fully resolved.
Charles Lamanna, Microsoft’s Executive Vice President of Copilot, Agents and Platform, said the company’s investigation had identified technical challenges and failure modes involving cascading failures and “thundering herds” at the network perimeter. He said Microsoft would publish a post-mortem covering the incident timeline and repair measures intended to prevent similar outages.
The company’s planned post-mortem will provide the next detailed account of how the network upgrade triggered the disruption, how recovery was managed and what changes Microsoft will make to reduce the risk of another large-scale service failure.
