Windows 11 March Update Breaks Microsoft Teams and OneDrive Sign-Ins

Microsoft has acknowledged a significant bug introduced by its March 2026 cumulative update that is preventing users from signing into Microsoft Teams Free, OneDrive, and several other Microsoft applications on Windows 11 devices.

The issue, tied to the KB5079473 update released on March 10, 2026, has left affected users locked out of their accounts despite having active internet connections.

Following the installation of KB5079473 (OS Build 26100.8037), a subset of Windows 11 users began experiencing sign-in failures for apps that rely on Microsoft account authentication.

Affected users are met with a misleading error message reading, “You’ll need the Internet for this. It doesn’t look like you’re connected to the Internet,” even when their devices are fully online and connected.

Microsoft confirmed the issue on March 19, 2026, just over a week after the update’s release, noting that the root cause is tied to a specific network connectivity state that the device enters post-update. The company is currently working on a fix expected within the next few days.

Affected Applications

The sign-in failure is not limited to Teams Free and OneDrive. Microsoft has confirmed the bug impacts any feature within an application that requires a Microsoft account sign-in, including:

• Microsoft Teams Free
• Microsoft OneDrive
• Microsoft Edge
• Microsoft Excel
• Microsoft Word
• Microsoft 365 Copilot

It is important to note that the issue is scoped specifically to Microsoft accounts (personal consumer accounts). Organizations using Entra ID, formerly Azure Active Directory, for enterprise authentication are not affected. This means most business and enterprise environments running Microsoft 365 through organizational credentials will continue to function normally.

Microsoft has confirmed the issue affects the following client platforms:

• Windows 11, version 25H2
• Windows 11, version 24H2

No server-side platforms are currently impacted.

Temporary Workaround

While Microsoft works toward a permanent patch, the company has provided a temporary workaround. Users experiencing this issue should restart their device while maintaining an active internet connection. This resets the problematic network connectivity state and typically resolves the sign-in failure.

However, there is a critical caveat: if the device is restarted without an internet connection, it may revert to the faulty connectivity state, causing the sign-in error to resurface. Users should ensure their device remains connected to the internet before and during the restart process to avoid retriggering the issue.

This bug is particularly disruptive for personal and small business users who rely on Microsoft’s free-tier services. Microsoft Teams Free, which targets individual users and smaller organizations that do not subscribe to Microsoft 365, is one of the most prominently affected applications.

For users who depend on OneDrive for file synchronization or Teams Free for communication, the sign-in barrier effectively renders these tools unusable until the patch arrives.

The March 10 Patch Tuesday update, KB5079473, was primarily a security and quality update, making this regression an unintended consequence of routine maintenance.

Microsoft has opened an official tracking page for the issue and confirmed it is actively investigating a resolution, with an update expected in the coming days.

Separately, Microsoft received reports from Samsung device users experiencing a complete loss of access to their C: drive following the February 2026 security update (KB5077181).

Affected users saw the error “C: is not accessible – Access denied”, which cascaded into app launch failures across Outlook, Office applications, web browsers, Quick Assist, and system utilities. In severe cases, users could not elevate privileges or uninstall updates.

Enterprise IT administrators deploying Windows updates via the Windows Update Standalone Installer (WUSA) may encounter failures when installing .msu files from a shared network folder containing multiple update files. The process returns an ERROR_BAD_PATHNAME message.

The issue does not occur when only a single .msu file is present in the shared folder, or when files are installed directly from a local drive.

Users are advised to monitor Microsoft’s Windows release health dashboard for the latest status.

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