Microsoft January 2026 Security Update Breaks Remote Desktop Credential Prompts

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Microsoft January 2026 Update Causes Remote Desktop Credential Failures Microsoft's January 2026 security update, KB5074109, has caused credential prompt failures for users accessing Azure Virtual Desktop and Windows 365 environments. The issue affects Windows 11 versions 24H2 and 25H2, leading to immediate sign-in failures for enterprise Remote Desktop infrastructure. An emergency update has been released to address this critical problem. 3 sources 31