Microsoft releases emergency Windows 11 update to fix Microsoft account sign-in bug

Microsoft has released an emergency out-of-band update for Windows 11 24H2 and 25H2 to fix a Microsoft account sign-in problem that appeared after the March 10, 2026 security update. The fix arrives in KB5085516 and moves affected systems to builds 26100.8039 and 26200.8039.

The issue caused some users to see a false “no Internet” error while signing in to apps with a Microsoft account, even though their devices were online. Microsoft says this blocked access to services and apps such as Microsoft Teams Free and OneDrive.

Microsoft also says the bug only affected Microsoft account sign-ins. Organizations that use Microsoft Entra ID for app authentication were not affected.

What KB5085516 fixes

According to Microsoft’s support bulletin, the problem started after Windows updates released on or after March 10, 2026. KB5085516 specifically fixes that sign-in failure for impacted Windows 11 users.

This is an out-of-band release, which means Microsoft pushed it outside the normal Patch Tuesday schedule. That usually happens when a bug causes a serious disruption and needs a faster fix. In this case, the problem could lock users out of core Microsoft services tied to personal accounts.

Microsoft’s Windows message center describes the same issue in similar terms, saying some users could not sign in to Microsoft apps and services after the March 2026 security update and would see a “no internet” message during sign-in.

Source: Microsoft support and Windows release health pages.

Who should install it

Users who installed KB5079473 and then had trouble signing in to apps with a Microsoft account should install KB5085516 as soon as possible. Microsoft directly links the sign-in issue to updates released on or after March 10, 2026, and KB5079473 is the March 10 cumulative update listed for these branches.

If your PC has the setting “Get the latest updates as soon as they’re available” turned on, Microsoft says the fix will arrive automatically. If that setting is off, you can install it manually through Windows Update.

Microsoft also made the update available through the Microsoft Update Catalog for manual deployment. That matters most for advanced users and IT admins who want to install the package directly or roll it out in managed environments.

What else is included

KB5085516 also includes refreshed AI component packages, but Microsoft notes that those components only apply to Windows Copilot+ PCs and will not install on standard Windows PCs or Windows Server systems. The updated components are Image Search, Content Extraction, and Semantic Analysis, all at version 1.2602.1451.0.

Microsoft also bundled a servicing stack update for Windows 11 version 24H2, listed as KB5083532 build 26100.8035. Servicing stack updates improve the part of Windows that installs future updates, which helps keep the update process stable.

At the time of publication, Microsoft says it is not aware of any known issues in KB5085516.

How to get KB5085516

• Open Settings
• Go to Windows Update
• Check the Optional updates available section
• Select Download & install if the update appears
• Advanced users and admins can also install it from the Microsoft Update Catalog

For managed devices, Microsoft says IT admins using Microsoft Intune or Windows Autopatch should use the expedited update guidance for out-of-band deployments.

FAQ