A code misconfiguration in the recent January 2026 Windows security update (KB5074109) caused intermittent connection failures for Cloud PC, causing those access requests to fail. The issue affected Windows App on specific Windows builds, causing sign-in failures.

Once our code fix had been deployed to address the offending misconfiguration, we recommended users or admins follow the Known Issue Rollback (KIR) instructions for resolving authentication errors and connection failures when connecting to Windows 365 Cloud PCs.

As of January 17, 2026, an out-of-band (OOB) update was released to fully resolve this issue, which is a streamlined and easier to follow mitigation action. For more information and installation instructions, refer to the public documentation on the public Windows Message center: https://learn.microsoft.com/windows/release-health/windows-message-center#3763

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