Published : 13 Nov 2026, 04:31 PM
Updated : 13 Nov 2026, 04:31 PM
Microsoft's global outage has disrupted email, workplace applications and artificial intelligence tools worldwide, with the technology giant struggling to restore normal operations after a series of server failures.
The problems began on Nov 12, affecting Outlook and several Microsoft 365 services, including Teams and the company's AI assistant Copilot.
Although engineers have reported improvements, the recovery process has been uneven, raising questions about how a failure within Microsoft's infrastructure could spread across so many applications.
What Went Wrong?
Microsoft has identified problems involving servers supporting Exchange Online, its cloud-based email platform, but has yet to establish the underlying cause.
According to the company's service-health updates, a large number of servers unexpectedly became unavailable, shifting additional traffic onto the remaining infrastructure.
This increased the pressure on functioning servers and contributed to widespread connectivity problems.
Importantly, Microsoft said the additional load was not caused by an overall increase in user traffic. Instead, fewer functioning servers were left handling the demand.
Engineers also investigated failures involving automated server-health checks and components responsible for processing connection requests.
The company has examined recent configuration changes as possible contributing factors, but has not confirmed that any particular change triggered the outage.
Why Were So Many Services Affected?
Microsoft's workplace applications share underlying systems, allowing problems with one service to disrupt functions in others.
Exchange Online, for example, provides the email and calendar infrastructure used by Outlook and several Microsoft 365 applications.
As a result, users experienced problems beyond sending and receiving emails.
Some Teams users encountered difficulties accessing calendars, scheduling meetings and managing invitations, while Copilot functions dependent on workplace data were also affected.
Microsoft's service notices identified problems involving other products, including SharePoint, Planner, To Do and certain security and administrative tools.
However, not every function stopped working.
The company said most core Teams features, including chats, calls and meetings, remained operational.
Why Has Recovery Taken So Long?
Restoring the affected servers has proved more complicated than simply restarting them.
Microsoft initially brought some servers back online, only for them to become unresponsive again when normal traffic resumed.
This forced engineers to investigate whether particular types of connections were overwhelming the infrastructure.
The company began redirecting traffic, temporarily restricting certain requests and rebuilding affected servers using earlier configurations.
By Friday, Microsoft reported improved stability after applying a patch to an authentication and routing component.
However, the company said the fix was being rolled out gradually, with engineers monitoring performance before restoring additional traffic.
Recovery efforts have also involved managing a backlog of delayed emails.
Microsoft extended its email timeout window to 48 hours to help preserve messages awaiting delivery.
Was it a Cyberattack?
Microsoft says it has found no evidence of malicious activity associated with the disruption.
The BBC reports that the company had ruled out a cyberattack, while Microsoft's own incident notices indicate that engineers were concentrating on infrastructure and connectivity failures.
However, the company has not yet published its definitive explanation of what caused the outage.
It says a detailed post-incident report will follow once services have been restored.
How Widespread Was the Disruption?
Outlook problem reports peaked at around 140,000 across 74 countries on Thursday, according to monitoring website Downdetector, as reported by the BBC.
The figures represent user-submitted reports rather than a confirmed count of affected customers.
Microsoft says more than 430 million people use its Microsoft 365 applications worldwide, although it has not established how many were affected by this outage.
The disruption spread to businesses, government agencies and healthcare providers.
Technology companies OpenAI and Anthropic also reported problems involving services connected to Microsoft's systems.
Australian cybersecurity expert Troy Hunt told the BBC that the incident demonstrated how heavily everyday activities still depend on email.
Beyond workplace communication, he pointed to its role in appointment confirmations, online purchases and account verification.
When Will Services Return to Normal?
Microsoft has not announced a definitive timetable for full restoration.
In its latest available updates on Friday, the company reported gradual improvements but warned that service performance remained inconsistent and infrastructure capacity had not returned to normal.
Engineers were continuing to restore affected servers in stages while monitoring traffic and processing delayed messages.
The incident has highlighted a broader vulnerability of cloud-based services: when multiple applications depend on the same infrastructure, a failure in one underlying system can disrupt seemingly unrelated functions.
For now, Microsoft has established how the disruption spread, but not what initially caused it.
