The March 2026 cumulative update for Windows 11, identified as KB5079473, has introduced a significant issue affecting user access to Microsoft Teams Free, OneDrive, and other applications. Users are experiencing difficulties signing into these services despite active internet connections.
Impact of KB5079473 on Microsoft Applications
The problem arose shortly after the update was released on March 10, 2026. Affected users, upon installing the update, encountered sign-in failures across various applications that require Microsoft account authentication. The error message misleadingly suggests a lack of internet connectivity, although devices are indeed online.
Microsoft acknowledged the issue on March 19, 2026, attributing it to a specific network connectivity state triggered by the update. The company assures users that a fix is underway and should be available soon.
Applications Affected by the Update
Beyond Microsoft Teams Free and OneDrive, the sign-in issue extends to numerous other applications such as Microsoft Edge, Excel, Word, and Microsoft 365 Copilot. Notably, only personal Microsoft accounts are impacted, leaving organizational accounts using Entra ID unaffected.
The problem is confined to Windows 11 versions 25H2 and 24H2, with no server-side platforms experiencing similar issues.
Temporary Solutions and Future Outlook
To mitigate the issue temporarily, Microsoft suggests restarting affected devices while ensuring they remain connected to the internet. This action typically resolves the connectivity problem, although a restart without an internet connection may reintroduce the error.
This disruption predominantly affects individual users and small businesses reliant on Microsoft’s free-tier services. As a result, applications like OneDrive and Teams Free are rendered ineffective until an official patch is released.
The KB5079473 update, intended as a security and quality enhancement, inadvertently caused this disruption. Microsoft is actively working on a resolution and expects to release an update shortly. Users should monitor Microsoft’s Windows release health dashboard for ongoing developments.
