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Microsoft confirmed an incident affecting search functionality across several Microsoft 365 services, including Outlook on the web, Outlook desktop, SharePoint Online, and OneDrive. The company said a recent deployment introduced a resource-utilization inefficiency on affected infrastructure, causing some users to experience degraded service. Microsoft tracked the issue as MO1456424 in the Microsoft 365 Admin Center and said it developed and deployed a fix to reduce resource pressure and restore normal operation.
User reports aligned with Microsoft's notice, with administrators describing failures opening SharePoint and OneDrive files, intermittent access to some SharePoint resources, Outlook connectivity issues, and related errors involving Copilot and slow Entra Conditional Access behavior. Reports suggested the disruption was partial rather than global, with symptoms concentrated in some environments and regions, including anecdotal reports from the Central and East US, while other users said their tenants were unaffected.
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Microsoft said it developed and deployed a fix intended to reduce resource pressure and restore service for affected Microsoft 365 users. The remediation was aimed at resolving the search issues in the impacted services.
Microsoft said a recent deployment introduced a resource utilization inefficiency that caused the Microsoft 365 search disruption. This provided the root-cause explanation for the incident tracked as MO1456424.
Microsoft identified an active incident, MO1456424, affecting search functionality for some users in SharePoint Online, OneDrive, Outlook on the web, and Outlook desktop. The company said the impact was limited to users served by affected infrastructure rather than a universal outage.
Early user reports described a possible Microsoft 365 outage affecting SharePoint and OneDrive, with SharePoint home pages loading but files failing to open and OneDrive showing the same error. The reports suggested possible impact in the Central and East US region, while at least one commenter said service was normal in New Zealand.
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Microsoft experienced a broad service disruption that affected **SharePoint**, **Teams**, **Excel**, the **Microsoft 365 Admin Center**, and Azure-hosted workloads, with users also reporting failures in **Dynamics 365**, **Dataverse**, Entra join operations, and administrative portals. Administrators said SharePoint timeouts, Teams image-loading failures, and unreachable Azure virtual machines were especially visible in **West US**, **Canada West**, and parts of **US East**, while Downdetector recorded a sharp spike in complaints. Microsoft acknowledged the incident and directed customers to service health alert `MO1437424`, saying it was investigating increased reports and reviewing telemetry to determine scope and impact. The disruption appeared to extend beyond core collaboration services into dependent platforms and Microsoft-backed update infrastructure. Sysadmins reported **Windows Media Creation Tool** failures with error `0x80072EE4 - 0x20000`, Windows feature enablement errors such as `0x80244022`, and **Windows Update** failures returning `0x801901f7` on newly imaged systems. A separate outage report also indicated **KaseyaOne** login issues that users linked to the Azure problems, suggesting downstream impact on third-party services hosted on Microsoft infrastructure as customers saw intermittent outages, degraded functionality, and some signs of partial recovery.
Jul 24, 2026
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.
Jun 29, 2026
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.
Jun 29, 2026