Microsoft has rolled out a new out-of-band Windows 11 update, KB5085516, designed to fix a frustrating Microsoft account sign-in failure that began after the March 10, 2026 cumulative update KB5079473. If you’re running Windows 11 version 24H2 or 25H2 and suddenly couldn’t sign in to apps even though your internet was working, this patch is the official remedy.
KB5085516 is available for Windows 11 24H2 and 25H2 and moves supported PCs to OS Build 26100.8039 (24H2) and 26200.8039 (25H2). Microsoft published the update on March 21, 2026, specifically to address a bug that could incorrectly report a “no Internet” error and prevent Microsoft account authentication in certain apps and services.
What the sign-in bug looked like for users
After installing KB5079473, some people found they couldn’t sign in to applications using a Microsoft account, despite having a stable internet connection. The issue could block access to Microsoft services and apps that rely on Microsoft account sign-ins, including Microsoft Teams Free and OneDrive. The misleading “no Internet” message made troubleshooting even more confusing, since the connection itself wasn’t actually the problem.
Important detail: this fix targets Microsoft account sign-ins, not Entra ID
Microsoft says the issue was limited to consumer-style Microsoft account sign-ins. Organizations using Microsoft Entra ID for authentication were not affected by this specific bug, which is useful to know for workplaces that authenticate through managed enterprise accounts rather than personal Microsoft accounts.
More than a one-off fix, but focused on the main problem
While KB5085516 includes the quality improvements from KB5079473, its primary purpose is to resolve the Microsoft account sign-in failure tied to updates released on or after March 10, 2026. In other words, this is a targeted repair update rather than a feature-focused release.
How to get KB5085516
Microsoft is delivering KB5085516 through Windows Update for devices that already installed KB5079473. If your PC is set to “Get the latest updates as soon as they’re available,” it should arrive automatically.
If you want to check manually, you can go to Settings, then Windows Update, and look for the update. Microsoft also offers a manual installation option through its official update catalog for anyone who prefers installing updates that way.
As of now, Microsoft says it isn’t aware of any problems with KB5085516. For Windows 11 users locked out of apps due to this Microsoft account sign-in issue, installing this out-of-band update is the clearest next step to restore normal access.
