Služba Microsoftu pro hostování a synchronizaci souborů.
Hello, thank you for reaching out to Microsoft Q&A.
Microsoft has acknowledged the issue and released a fix for Windows 11 devices. This confirms that the problem is related to the March security updates you installed on March 10, 2026—KB5079473 (OS Builds 26200.8037 and 26100.8037).
So, before you do anything,
Go to Start > Settings > Update & Security > Check for updates.
See if you might have KB5085516 available to install. (or) Install all the updates available for your device.
Once installed, try signing in with your Microsoft account.
For reference:
21. března 2026 – KB5085516 (buildy operačního systému 26200.8039 a 26100.8039) mimo pásmo