The Microsoft outage that began on Thursday, 12 November 2026 disrupted Outlook, Teams and Copilot for users worldwide, and Microsoft was still restoring Exchange Online on Friday, 13 November 2026.
According to Reuters, Microsoft said the problems were “primarily issues with Exchange Online”, the cloud service behind email and calendars in Microsoft 365. Downdetector, a site that tracks outage reports, logged a peak of 138 058 Outlook reports at about 13:00 US Eastern time (20:00 SAST) on Thursday, falling to about 34 490 by evening.
What caused the Microsoft outage?
Microsoft first blamed heavy demand on the infrastructure behind Exchange Online across several regions, then clarified that more traffic was not the cause. In a post on social media, it said the strain came from “a number of servers being unexpectedly unavailable”.
Exchange Online is Microsoft’s cloud version of the mail server software that many companies once ran themselves. When some of its servers drop out, the rest absorb their traffic and can buckle in turn, which can stall recovery.
Earlier on Thursday, 12 November 2026, Microsoft said it had paused all deployments, moved additional traffic off the affected infrastructure and begun restarting affected servers to return them to service. It described the effort in a post on social media:
We’re aggressively pursuing all pathways to reduce impact.
Which services did the Microsoft outage hit?
Microsoft’s status notices listed Exchange Online mailboxes, which people reach through Outlook on the web, the desktop app and mobile. Teams calendars and meeting scheduling, Copilot, SharePoint features that depend on Exchange, Defender, Intune, Planner, To Do and Power BI were also affected. Microsoft said features that do not depend on Exchange Online kept working.
Microsoft tracks the Exchange Online incident as EX1550543 and the wider Microsoft 365 incident as MO1550821. OpenAI said new connections to its Microsoft 365 tools might break, and Anthropic said an upstream provider issue was affecting its Microsoft 365 connector.
Microsoft outage timeline in South African time
Microsoft first posted shortly before 13:00 US Eastern time on Thursday, 12 November 2026 (20:00 SAST) that it was investigating reports of users unable to reach Exchange Online mailboxes in the Americas. By 17:47 US Eastern time (00:47 SAST on Friday), Microsoft 365 reports had fallen to nearly 13 000.
At about 23:30 US Eastern time on Thursday (06:30 SAST on Friday, 13 November 2026), Microsoft said partial recovery in the regions where it had applied adjustments was not becoming sustained recovery. It said on Friday that it was increasing virtual machine capacity and investigating traffic-routing problems that had blocked a lasting fix.
Executive Vice-President Charles Lamanna said the outage was not caused by a cybersecurity breach. Microsoft’s status notices were still open on the morning of Friday, 13 November 2026, with no estimated time for full recovery.
Who else felt the Microsoft outage?
Microsoft’s cloud has failed before, including an Azure outage on Wednesday, 29 October 2025 and a global outage on Friday, 19 July 2024. Electric truck maker Workhorse Group has now moved its third-quarter results from Thursday, 12 November 2026 to Monday, 16 November 2026, citing disruption from the outage.
