Microsoft confirms that the September 2026 security updates trigger Remote Desktop Services failures across Windows Server 2012-era servers and Windows 10/11 clients.

Enterprises can mitigate by applying known issue rollback Group Policy packages, or temporarily restoring RDS connectivity by restarting affected VMs or rolling back the updates, though removing updates also removes the security fixes from Patch Tuesday.

Symptoms include RDS instability, failed or hanging RDP connections, sign-ins getting stuck, servers lingering at 'Please wait for the Remote Desktop Configuration,' and tools like MMC, RDS Licensing Diagnoser, and File Explorer becoming unresponsive; the Windows Update page itself may stall.

Microsoft notes a prior, similar RDS issue resolved in March 2025 tied to updates since January 2025, and the current widespread reports are now accompanied by official remediation guidance.

A set of known-issue rollback Group Policy templates is provided as mitigations, covering multiple Windows versions including Windows 11 26H1/25H2/24H2, Windows 10 21H2/22H2, Windows Server 2025/2022, Windows Server 2012/2012 R2, and older Windows 10/1809/2016 builds.

Existing RDP sessions may not disconnect or log off properly, and new connection attempts can fail after hanging during the connection process.