New Delhi: Thousands of users across several countries faced disruptions to Microsoft services on Thursday, November 12, as a widespread outage affected Outlook, Microsoft 365, Teams, Copilot and other workplace applications. Users reported difficulties accessing email inboxes, sending and receiving messages, logging into accounts and connecting to cloud-based services.

Microsoft acknowledged the disruption and said it was working to restore affected infrastructure. The company identified unexpected server outages and connectivity problems, warning that some servers became unresponsive again after being returned to service.

Users in 72 countries reported problems involving Microsoft services, including Teams, Copilot, OneDrive and Azure. The disruption also affected several security, administration and compliance products used by businesses.

Full list of Microsoft services affected

Microsoft said users might be unable to connect to multiple Microsoft 365 services. The list of affected products included:

  • Exchange Online: Microsoft’s hosted email service, affecting access to mailboxes.
  • Microsoft Teams: Workplace messaging, meetings and collaboration.
  • SharePoint Online: Document management and team collaboration.
  • Microsoft Copilot 365: AI-powered assistance integrated with Microsoft 365 applications.
  • Microsoft Defender XDR: Security monitoring and threat detection.
  • Microsoft Planner: Task and project management.
  • Microsoft To Do: Personal task and reminder management.
  • Microsoft Intune: Device and application management.
  • Microsoft Defender for Office 365: Security protection for email and collaboration tools.

Several Microsoft Purview services were also affected. These included authorisation, automatic labelling, data loss prevention (DLP), communication compliance and data classification.

Other services, including Cloud Update, Cloud Policy and Inventory, were also reported to have experienced disruptions.

The impact varied across products, and not every user necessarily experienced problems with every service.

Outlook outage reports surge on Downdetector

Outlook was among the most heavily affected services. Users reported that their inboxes would not load, emails could not be sent or received, and some account connections failed.

According to the Associated Press, nearly 1.3 lakh users had reported Outlook access problems on Downdetector shortly after 1 pm Eastern Time on Thursday. The number of reports subsequently declined, although users continued to flag connectivity issues.

Reuters also reported a sharp increase in complaints involving Microsoft 365 and Teams. Downdetector figures represent user-submitted reports rather than a confirmed count of affected customers.

Microsoft initially acknowledged problems accessing Exchange Online mailboxes through multiple connection methods in the Americas. It later indicated that the disruption could affect connectivity in other regions as well.

Why did Microsoft services stop working?

Microsoft said a portion of its infrastructure was experiencing elevated load, contributing to connectivity errors. The company also identified servers that had unexpectedly become unavailable after failing automated health checks.

The restoration process proved challenging because some servers that initially returned to service became unresponsive again when they started receiving traffic.

In an update, Microsoft said it was analysing diagnostic data with its networking and platform experts to determine what was triggering the behaviour.

The company introduced protective traffic-management measures and temporarily restricted certain types of traffic reaching affected infrastructure in specific locations. It also began rebuilding a subset of affected servers using an earlier configuration to check whether that would prevent them from becoming unresponsive.

Microsoft said it was pursuing a gradual restoration of services rather than immediately directing all traffic back to the affected systems.

OpenAI and Anthropic services also experience disruption

The outage’s impact extended beyond Microsoft’s own applications. Services operated by other technology companies that rely on Microsoft infrastructure also experienced problems.

OpenAI said it was investigating an issue involving its Microsoft connectors. New connections could fail, and some tools might not work as expected.

Anthropic also reported a problem with an upstream provider affecting its Microsoft 365 connector.

The disruptions highlighted how problems at a major cloud and workplace technology provider can affect other companies whose products depend on its infrastructure.

Amazon, meanwhile, said its services were operating normally and described reports linking its systems to the disruption as inaccurate. The company said an unrelated internet disruption elsewhere was prompting some misleading reports.

When will Microsoft services return to normal?

Microsoft began restoring affected servers, redirecting traffic and implementing additional measures to reduce the impact. However, the company cautioned that recovery could take time because some infrastructure became unresponsive after traffic returned.

Downdetector reports declined from their earlier peaks, indicating that the number of reported problems was easing. However, falling complaint numbers do not necessarily mean that every affected service has been fully restored.

For businesses and individual users, the incident underlined the importance of having alternative communication channels and business continuity arrangements when essential cloud-based services become unavailable.

Microsoft’s investigation into the server behaviour remains important to understanding the underlying cause. The company has not established a confirmed root cause in the updates cited in the report, and there was no verified indication in those updates that the disruption was caused by a cyberattack.

The outage demonstrated the dependence of businesses on interconnected cloud platforms. Even a disruption affecting part of a provider’s infrastructure can interrupt email, collaboration, security management and AI-powered services across multiple organisations.