Microsoft 365 and Teams Outages Due to Infrastructure Issues
Microsoft Teams experienced widespread outages, with users across the United States, Europe, and other regions reporting delays in sending messages and problems with other service functions. Microsoft acknowledged the issue publicly, stating that they were investigating the cause and observing signs of recovery, but did not initially provide a root cause or timeline for full restoration. The outage disrupted communication for many organizations relying on Teams for collaboration and messaging.
Separately, a significant outage affected Microsoft 365 services—including Teams, Outlook, OneDrive, and the Copilot AI assistant—in Japan and China. This disruption was traced to a critical routing misconfiguration in Microsoft's infrastructure, which isolated healthy systems and led to intermittent login failures, degraded performance, and app loading errors. Microsoft confirmed that the incident was not the result of a cyberattack and reported that engineers had rebalanced traffic to restore service, with no data loss or security breaches identified. The outages caused notable business disruption in the affected regions, particularly for organizations dependent on Microsoft’s cloud ecosystem for daily operations.
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How this story unfolded
4 events from the most recent confirmed update back to the earliest known activity.
Microsoft confirms Teams outage and opens investigation
Microsoft publicly acknowledged the Teams incident on X, saying it was investigating the disruption, identifying affected scenarios, and reviewing telemetry that showed some signs of recovery. The company said further updates would follow as it worked to determine the root cause.
Microsoft Teams outage begins across the US and Europe
A separate widespread Microsoft Teams outage started at 14:30 ET, affecting users in multiple regions including the United States and Europe. Users reported problems such as delayed message delivery.
Microsoft mitigates Asia-Pacific outage by rebalancing traffic
Microsoft engineers responded to the Asia-Pacific service disruption by rebalancing traffic across redundant systems, leading to partial recovery within hours. The company said there was no evidence of a cyberattack, data loss, or security breach and continued monitoring pending full restoration.
Microsoft 365 and Copilot outage hits Japan and China
A major Microsoft 365 outage began around 00:00 UTC, disrupting Outlook, Teams, OneDrive, and Copilot for users in Japan and China. Microsoft said the incident was limited to the Asia-Pacific region and caused login failures, degraded performance, and app loading errors.
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Microsoft cloud service disruptions affecting Microsoft 365, Exchange Online, and Windows Update/Store
Microsoft reported multiple **service-impacting incidents** across its cloud ecosystem. Administrators in **North America and Canada** experienced an outage and degraded performance in the **Microsoft 365 admin center**, with some users also unable to access the *M365 app* or raise support tickets; Microsoft said it was analyzing telemetry, usage patterns, and **CPU utilization**, and reviewing user-provided **HAR files** to isolate the root cause. Separately, **Exchange Online** quarantined legitimate messages after an updated **URL rule** incorrectly marked some URLs as phishing, disrupting email flow for affected customers while Microsoft worked to release quarantined mail and unblock legitimate URLs. In another disruption, Microsoft attributed **Windows Update** and **Microsoft Store** failures/timeouts (notably impacting Windows 11 users) to a **utility power interruption** at a **West US datacenter**, which cascaded into issues with **Azure storage clusters** supporting content delivery; backup power engaged and power was later stabilized, but service recovery required additional remediation beyond restoring electricity.
Mar 21, 2026
Microsoft 365 Disruptions: Exchange Online False-Positive Phishing Blocks and Microsoft Teams Service Degradation
Microsoft reported a Microsoft 365 security-service failure in which **Exchange Online** anti-phishing heuristics incorrectly classified thousands of legitimate URLs as credential-phishing, leading to quarantined emails, blocked link access, and removal of messages via automated actions (including ZAP) across **email and Microsoft Teams**. The incident (tracked as `EX1227432`) ran from Feb 5 to Feb 12 and generated false XDR-style alerts such as “potentially malicious URL click was detected”; Microsoft attributed the impact to a **logic error** in newly updated heuristic detection, with additional tooling and a separate signature-system bug compounding and delaying rollback. Separately, Microsoft also worked an active **Microsoft Teams** outage/service degradation (tracked as `TM1233974`) affecting some users in the **United States and Europe**, with delays/failures sending and receiving chats that include inline media and issues joining meetings or signing in. A third item—abuse of **Atlassian Jira Cloud** notification emails to deliver localized scam lures and redirect victims to casino/investment fraud—describes a distinct threat campaign unrelated to the Microsoft 365 incidents and should be treated as a separate story.
Mar 21, 2026
Microsoft Azure and Microsoft 365 Global Outage Due to DNS Issues
Microsoft experienced a widespread outage impacting Azure, Microsoft 365, and related services, affecting customers and organizations worldwide. The disruption began around 16:00 UTC and was attributed to DNS issues, resulting in degraded availability for services such as Azure Front Door, the Azure Portal, Intune, Exchange admin center, and authentication services. Major companies and sectors, including payroll providers, healthcare organizations, and the Dutch railway system, reported significant operational impacts, with users unable to log in or access critical business platforms. Microsoft acknowledged the outage, provided mitigation advice such as using programmatic access methods and failover strategies, but did not immediately offer an estimated time for resolution. The outage's effects were felt across a broad spectrum of industries, with reports of internal workflow disruptions and delays in essential services like payroll processing. Microsoft advised customers to consider implementing failover strategies using Azure Traffic Manager and to monitor the Azure status page for updates. The incident highlighted the critical dependency of global businesses on Microsoft's cloud infrastructure and the cascading impact of DNS-related failures on authentication and service availability.
Mar 21, 2026