connection failures

Windows administrators are experiencing significant challenges with Remote Desktop Services (RDS) following the installation of the September 2026 cumulative updates for Windows Server versions 2019, 2022, and 2025. Users are unable to connect, and some require a hard reset to regain functionality. Reports indicate that RDS servers initially function well but fail after a few hours, with existing sessions struggling to disconnect and new connections failing. Administrators have noted that issues arise after user logouts, leading to service crashes and deadlocks between Remote Desktop and the Local Session Manager. Microsoft has not confirmed the cause of these failures, which affect all mentioned Windows Server releases. Some administrators have restored functionality by rolling back the updates, but this also removes important security fixes. Microsoft is investigating the issue and will provide guidance.