Windows Server Remote Desktop broken by September security patches
Microsoft acknowledged that its September 2026 security updates are causing Remote Desktop Services to become unstable on Windows Server and client systems. Administrators report failed RDP connections, sign-in issues, and servers hanging during configuration. The company has issued a Group Policy workaround for affected enterprise-managed devices.
The problem stems from this month's Patch Tuesday release and spans a wide range of systems, from Windows Server 2012 through Windows Server 2025, along with Windows 10 and 11 clients. Administrators report that RDP connections drop after several minutes, sign-in attempts stall, and servers freeze at the Remote Desktop Configuration screen. Once failures begin, existing sessions may refuse to disconnect cleanly, and new connection attempts hang as well.
Microsoft has published version-specific Group Policy mitigations for enterprise-managed devices, while those unable to connect through RDP can temporarily restore service by restarting the affected virtual machine. Rolling back the updates removes the security protections included in this month's release. This follows a similar RDS-related known issue that Microsoft addressed in March 2025 after updates released since January of that year.
This disruption could significantly hamper organizations that depend on remote access to Windows servers, potentially stalling workflows for IT teams and remote employees. Businesses lacking on-site access to affected machines may face extended downtime while awaiting Microsoft's permanent fix. Smaller organizations without dedicated IT staff may struggle to apply the Group Policy workarounds, leaving them caught between connectivity failures and unpatched security vulnerabilities.