A large-scale outage has disrupted access to Outlook and several Microsoft 365 services since Thursday, November 12, 2026.Users are struggling to view or send their emails, while businesses and administrations report difficulties.
More than 130,000 problems were reported in the United States at the peak of the incident. Microsoft said Friday morning that partial improvement was observed, without announcing a complete recovery.
The disruption, initially reported on the American continent, has also been observed in other regions, notably Europe and Asia. According to Deutsche Welle, Downdetector collected reports from 74 countries and territories in around an hour.
This data measures the distribution of reports, not the number of people actually affected.
More than 130,000 Outlook reports in the United States
The wave of difficulties intensified on Thursday, November 12 around 1 p.m. on the East Coast of the United States, i.e., 7 p.m. in Tunisia. According to Downdetector figures cited by Reuters, the number of reports concerning Outlook exceeded 130,000 at the peak of the incident in the United States. Thousands more reports concerned Microsoft 365 and Teams.
This data requires an important caveat: a report does not equal a unique user, and it is not a global tally. They nonetheless provide an indication of the scale of the outage and its rapid spread.
The most common symptoms include the inability to open an inbox, login errors, the failure of certain messaging operations, and delays in email delivery.
Outlook, Teams, Copilot: which services are actually affected?
The core of the problem lies in Exchange Online, the hosted mail service used by many businesses and organizations. Microsoft reports difficulties accessing Outlook on the Web, Outlook on desktop, and mobile or app connections that rely on Exchange Online.
The outage also affects other products connected to this infrastructure. Some features of Microsoft 365, the admin center, Copilot, Microsoft To Do, Planner, and Microsoft Defender for Office 365 are affected. External sharing functions on SharePoint may also be disrupted.
Teams is not completely down. In its technical bulletin, Microsoft states that essential functions, including most calls, meetings, and conversations, remain operational. However, tasks that depend on Exchange Online, such as calendar management, some invitations, and meeting planning, can fail.
This distinction is crucial: the incident does not imply that all Microsoft software is inaccessible, nor that all of their users are experiencing the same difficulties.
Why is Microsoft struggling to bring the servers back online?
Initial investigations showed that a portion of the group’s servers became unavailable, causing traffic to be redirected to the remaining active machines. This increased their load and fueled connection errors. In some cases, rebooted servers stopped responding again when traffic returned.
In its technical bulletins, Microsoft cites malfunctions of components used to establish secure connections and to route requests. The company redirected part of the traffic, rebooted servers, increased capacity, and tested configuration changes.
In its update on Friday, November 13 at 7:25 UTC, i.e., 8:25 in Tunis, Microsoft reports initial positive results after applying a fix related to authentication and routing on part of its infrastructure. The fix still needs to be extended and its stability verified. No timeframe for a complete return to normal has been announced in this bulletin.
Microsoft also states that at this stage there is no indication that malicious activity is the cause of the outage. The definitive cause remains to be determined and will be the subject of a technical report after the incident. It would therefore be premature to attribute this outage to a cyberattack or to a particular update.
Public administrations, airlines and companies disrupted
The impact extends beyond individual inboxes. According to the Associated Press, the government agency in charge of technology in Singapore reported disruptions to administrative email systems. In the Philippines, the Supreme Court reported effects on some of its operations, notably email responses. In Japan, authorities stated that government IT systems had been affected.
In India, Air India temporarily redirected its email services to continue receiving customer requests. IndiGo also reported difficulties with its email support. Both airlines said their flight operations were not affected.
The outage also affected Microsoft 365 connectors used by AI services, notably those from OpenAI and Anthropic, according to Reuters and the Associated Press. It illustrates the dependency of many professional services on the same email and digital identity infrastructure.
What consequences for users in Tunisia?
Tunisia-based businesses, educational institutions and administrations using Exchange Online and Microsoft 365 are also affected by this international incident. Communications with foreign clients or partners, meeting invitations, and certain collaborative work tasks may be delayed.
However, No country-specific figures for Tunisia are available in the sources consulted. It would not be accurate to claim that all Outlook mailboxes in the country are affected. The impact depends on the services used, the regions, and the infrastructure of each organization.
What to do if your Outlook mail is not working?
Check the status of Microsoft services first. A concurrent access error affecting several colleagues may be part of the general incident rather than a problem on your computer or phone.
Avoid unnecessary changes. Deleting an account, changing server settings, or reinstalling Outlook will not resolve an outage located in Microsoft’s infrastructure. Administrators can consult the Microsoft 365 service health center; incident references are EX1550543 for Exchange Online and MO1550821 for other services.
For urgent messages, temporarily use another suitable communication channel, for example a phone call or another secure professional channel. Before resending an important email, check its sending status to avoid duplicates when the service resumes.
To place this episode in context, Tunisie Numérique had already reported a global Microsoft outage in January 2023.
