Microsoft has acknowledged that the September 2026 security updates are causing widespread Remote Desktop Services (RDS) failures across Windows Server, Windows 10, and Windows 11 systems.
- September 2026 security updates are causing RDS instability and connection failures.
- Affected systems include Windows Server 2012 and later, as well as Windows 10 and 11.
- Microsoft has released specific Group Policies to mitigate the issue for enterprise environments.
Microsoft has officially confirmed reports that the September 2026 security updates are causing significant failures in Remote Desktop Services (RDS) across various Windows environments. The issue, highlighted in a recent release health update, impacts a wide range of systems, including Windows Server 2012 and newer versions, alongside Windows 10 and Windows 11 devices.
System administrators have reported widespread issues following the installation of this month's Patch Tuesday updates. Common symptoms include the inability to establish new RDP connections, sign-in failures, and servers becoming stuck on the 'Please wait for the Remote Desktop Configuration' screen. In some severe instances, a hard reset of the system is required to restore basic functionality.
Why This Matters
BozokMedia analysis shows that these RDS failures can paralyze enterprise operations, particularly for organizations relying heavily on remote management and virtualized environments. The inability to access servers remotely can lead to massive downtime and delayed response times for critical IT infrastructure.
The failure of Remote Desktop Services during a security patch cycle creates a dangerous paradox where the attempt to secure a system actually compromises its availability.
Beyond connection issues, the bug also renders essential administrative tools unresponsive. Users have noted that the Microsoft Management Console (MMC), RDS Licensing Diagnoser, and even File Explorer may stop responding. Furthermore, the Windows Update page itself has been reported to hang indefinitely on a loading indicator.
Historical Background
This is not an isolated incident for the tech giant. Microsoft faced a strikingly similar issue in March 2025, where updates released since January 2025 triggered comparable Remote Desktop and RDS connection failures. This recurring pattern highlights the complexities of deploying security patches across such a diverse ecosystem of legacy and modern operating systems.
Mitigation and Solutions
To combat these failures, Microsoft has provided specific Group Policies that IT departments can use to mitigate the issue on managed devices. These policies vary depending on the specific version of Windows being used.
| Affected OS Version | Mitigation Group Policy (KB) |
|---|---|
| Windows 11 26H1 | KB5124012 |
| Windows Server 2022 | KB5123066 |
| Windows Server 2012 | KB5123065 |
For those unable to apply Group Policies immediately, Microsoft suggests that stopping and restarting affected virtual machines may temporarily restore connectivity. While rolling back the buggy updates is an option to restore functionality, administrators are warned that doing so will remove critical security fixes provided in the latest Patch Tuesday release.
Frequently Asked Questions
Question 1: Will this affect my home Windows 11 PC?
Answer: Yes, the report indicates that Windows 10 and Windows 11 devices are also susceptible to these RDS-related instabilities.
Question 2: Is it better to roll back the update or wait for a fix?
Answer: Rolling back restores access but leaves you vulnerable to security threats. It is recommended to use the provided Group Policy mitigation if possible.
