Global Microsoft 365 failure leaves employers without email and chat, testing HR business continuity plans
A global Microsoft outage has left businesses around the world struggling to send and receive email, after a failure across Microsoft 365 knocked out access to Outlook, Teams and other workplace tools on Thursday 12 November 2026 (US time), or early Friday 13 November in Australia.
The disruption began at 11:17am US Eastern Time, about 3:17am AEDT, according to Microsoft incident logs republished by the University of Pennsylvania's Microsoft incident reports page. By about 4:30am AEDT, more than 120,000 users had reported problems accessing Outlook on outage tracker Downdetector, a site that aggregates user-submitted fault reports, ABC News reported. Reports peaked at more than 131,000, according to TechRadar's live coverage.
At the time of writing, Microsoft had not published a resolution time or a confirmed root cause.
What happened in the Microsoft 365 outage?
On its Microsoft 365 service health status page, the company labelled the incident "service degradation" and warned that "users may be unable to connect to multiple Microsoft 365 services". Services listed as potentially affected included Exchange Online (the cloud email service behind business Outlook accounts), Microsoft Teams, SharePoint Online, Microsoft Copilot 365 and Microsoft Defender XDR. Microsoft Planner and Microsoft To Do were later added to the list.
Microsoft said the problem was not caused by a surge in demand.
"We've determined that the elevated load isn't driven by an overall increase in traffic, but by a large number of servers being unexpectedly unavailable, which is shifting load onto the remaining infrastructure," the company said in a status update. "We're investigating what's causing these servers to become unavailable while we work to safely return them to service."
In a later update, Microsoft said "the failed health checks may originate from a specific component that's responsible for processing server health", adding that it had "not identified any recent change correlated with the start of impact".
The company said it was "aggressively pursuing all pathways to reduce impact", and that it had paused all deployments, moved traffic off the affected infrastructure and begun restarting servers, according to a post from the Microsoft 365 Status account on X.
The knock-on effects extended beyond Microsoft's own apps. OpenAI said it was investigating broken Microsoft connectors, while Anthropic said an issue with an upstream provider was affecting its Microsoft 365 connector, ABC News reported, citing AP and Reuters.
Separately, Microsoft said earlier on Thursday (US time) that it had restored a shorter Teams disruption in North America, although some users continued to report connectivity issues, The Guardian reported.
Why an Outlook outage hits business operations so hard
For most organisations, Outlook is not just an inbox. It is the calendar that holds interviews and performance reviews, the channel for payroll approvals and supplier invoices, and the record of decisions made with clients and staff.
The scale of that dependence is large. Microsoft reported in January 2026 that the number of paid commercial Microsoft 365 seats "now exceeds 450 million", according to Office 365 for IT Pros' analysis of Microsoft's FY26 Q2 results. Microsoft said commercial seats grew a further 5 per cent in its FY27 first quarter, reported in October 2026, though it did not publish an updated total. Most of those business plans include Exchange Online and Outlook. Microsoft has not updated its Teams figure of 320 million monthly active users since October 2023, the same analysis noted.
Microsoft's own research shows how central email is to the working day. Its June 2025 Work Trend Index special report found the average worker receives 117 emails a day, that Microsoft 365 users are interrupted roughly every two minutes by a meeting, email or notification, and that around 40 per cent of people online at 6am are reviewing email to set the day's priorities, TechSpot reported.
When both email and Teams fail at once, as in this outage, employees lose their two main channels for raising problems, which leaves HR and managers with few ways to reach staff.
What HR leaders should do during a Microsoft outage
The outage is a reminder of lessons many employers learned when a global IT outage proved a wake-up call for employers and business leaders in July 2024. The following are practical steps for HR teams:
- Switch to a backup channel. Use SMS, phone trees or a non-Microsoft messaging tool to tell staff what is happening and what is expected of them, especially those starting early in Asia-Pacific time zones.
- Protect time-critical processes. Check whether payroll approvals, rosters, contract signings or termination meetings scheduled through Outlook need a manual workaround or a new date.
- Reschedule candidates and new starters. Interviews and onboarding sessions run through Teams or Outlook invitations may have failed silently. Contact candidates directly rather than assuming they received updates.
- Set fair expectations on productivity. Staff should not be penalised for missed deadlines caused by the outage. Managers should also avoid a flood of late-night catch-up emails, particularly in Australia, where right to disconnect laws took effect for most employers in August 2024.
- Warn staff about scams. High-profile outages can be used as cover for phishing emails posing as IT support or password-reset requests. Remind employees to verify any such message through a separate channel.
- Review the continuity plan afterwards. Record which tasks stalled, how long staff were out of contact and which workarounds held up. Recognise the people who kept things moving: Delta Air Lines rewarded employees for their response to the global IT outage in 2024.
