Microsoft's September security update caused Remote Desktop Services to fail on some Windows Server systems, and an emergency fix is now available.
- What it is: The September Windows security update introduced a fault that could stop Remote Desktop Services from responding, blocking new remote sessions and, in some cases, preventing local and remote sign-in altogether. The same update also broke shared folders in Hyper-V Linux virtual machines and caused some USB audio devices to fail.
- Who is affected: Businesses running Windows Server 2022 or 2025, or Windows 10/11 devices, that installed the September 8 security update and rely on Remote Desktop for remote access or terminal services.
- What the risk is: A server that can no longer accept Remote Desktop connections can lock staff and IT support out of remote administration until the issue is resolved.
- What to do: Install the out-of-band update released on 14 September (via Windows Update or WSUS), which supersedes the September 8 release and fixes all three issues.
If your business relies on Remote Desktop Services for remote work or IT support access, we recommend confirming this update has been applied before your next scheduled maintenance window.
Source: BleepingComputer