Windows 11 KB5085516 update to fix Microsoft account sign-in failures

Microsoft has released KB5085516, an out-of-band update for Windows 11 24H2 and 25H2, taking affected systems to OS Builds 26100.8039 and 26200.8039. The patch was published on March 21, 2026, and is aimed at fixing a Microsoft account sign-in problem that appeared after the March 10 cumulative update KB5079473.

According to Microsoft, the issue could stop some users from signing in to apps with a Microsoft account even when the PC had a working internet connection. The company says the bug could trigger a false “no Internet” error and block access to Microsoft services and apps, including Microsoft Teams Free and OneDrive.

The fix targets Microsoft account sign-ins, not Entra ID

Microsoft says the problem only affected sign-ins that use Microsoft accounts. The company adds that organizations using Microsoft Entra ID for app authentication were not affected by this specific issue.

KB5085516 also carries over the quality improvements from KB5079473, but its main purpose is to resolve the sign-in failure tied to updates released on or after March 10, 2026. That makes this a targeted repair release rather than a broader feature update.

How Microsoft is delivering KB5085516

Microsoft says the update is being offered through Windows Update for devices that have already installed KB5079473, and it is also available as a manual download from the Microsoft Update Catalog. PCs with “Get the latest updates as soon as they’re available” turned on should receive it automatically, while others can install it manually through Settings > Windows Update.

Microsoft’s support page also says it is not currently aware of any issues with KB5085516. That gives Windows 11 users dealing with Microsoft account sign-in failures a clear official next step, especially if they were affected by the March Patch Tuesday release.