Microsoft has acknowledged that its September 2026 security patches are triggering Remote Desktop Services (RDS) failures across Windows Server deployments. The company issued a release health notice on Friday documenting the problem, which affects Windows Server 2012 through current versions alongside Windows 10 and Windows 11 client systems.

The issue emerged after widespread complaints from Windows administrators reporting that applying this month's Patch Tuesday updates prevents RDP access and sometimes necessitates hard reboots to restore service. Microsoft stated that "in some environments, RDS might become unstable, resulting in RDP connections failing after several minutes, sign-in issues, or servers hanging at 'Please wait for the Remote Desktop Configuration'."

Beyond RDS problems, the patches also render related utilities unresponsive. According to Microsoft, "related tools, including Microsoft Management Console (MMC), RDS Licensing Diagnoser, and File Explorer might also become unresponsive. Additionally, the Windows Update page might stop responding and continuously display a loading indicator."

Administrators encountering the problem have documented additional complications: existing Remote Desktop sessions fail to disconnect or log off cleanly, and fresh connection attempts hang during the authentication phase before ultimately failing.

Mitigation and Workarounds

Microsoft has released Group Policy settings to address the issue on enterprise-managed systems. These policies are located under Computer Configuration > Administrative Templates and correspond to specific Windows versions and patch levels:

  • Windows 11 26H1: KB5124012 260912_00471 Group Policy
  • Windows 11 25H2 and Windows 11 24H2: KB5124008 260911_19322 Group Policy
  • Windows 11 23H2: KB5122880 260912_00473 Group Policy
  • Windows 10 21H2 and 22H2: KB5122878 260911_18476 Group Policy
  • Windows Server 2025: KB5122871 260911_18472 Group Policy
  • Windows Server 2022: KB5122882 260911_18471 Group Policy
  • Windows 10 1809 and Windows Server 2019: KB5122876 260911_18474 Group Policy
  • Windows 10 1607 and Windows Server 2016: KB5123099 260911_18473 Group Policy
  • Windows Server 2012: KB5123065 260911_18475 Group Policy
  • Windows Server 2012 R2: KB5123066 260911_18477 Group Policy

For those unable to reach affected virtual machines via RDP, Microsoft suggests that stopping and restarting the VM may temporarily restore RDS connectivity while a permanent solution is developed.

Some administrators have successfully regained Remote Desktop functionality by uninstalling the problematic updates. This approach carries a trade-off, however: removing the patches also eliminates the security protections bundled with this month's Patch Tuesday release.

This incident echoes a comparable problem Microsoft addressed in March 2025, when Windows updates released between January and March 2025 similarly broke Remote Desktop and RDS connectivity.