Summary: Microsoft confirms RDS failures following September 8 security updates. A permanent fix remains pending. Successful patch installation alone cannot validate a session host.
Connections can fail after several minutes
According to Windows Release Health, RDP sessions can disconnect, sign-ins fail or servers stall during Remote Desktop configuration. MMC, Licensing Diagnoser, Explorer and Windows Update can also become unresponsive. Microsoft opened the issue on September 11 and added it to the KB article on September 12.
Microsoft lists Windows Server 2012 through 2025, including 2012 R2, plus several Windows 10 and 11 versions. This does not mean every installation fails. For two common server releases, the originating updates are:
| System | Update | Build |
|---|---|---|
| Windows Server 2022 | KB5122882 | 20348.5622 |
| Windows Server 2025 | KB5122871 | 26100.33438 |
“Mitigated” does not mean fixed
For VMs inaccessible through RDP, the status portal suggests stopping and deallocating the machine, then starting it again, as a possible temporary recovery. Microsoft promises neither guaranteed recovery nor a lasting fix. The KB article directs administrators needing immediate assistance to business support.
As of September 14, Microsoft still plans a resolution in a future Windows update. The reviewed notices provide neither a technical root cause nor a release date.
Pandorex assessment
RDS pilot testing should therefore include a sustained session, another sign-in and management tools. A brief connection check immediately after reboot can miss a delayed failure.
This adds a subsequently confirmed operational issue to our September Patch Tuesday report. Matching symptoms warrant checking installed updates early in diagnosis. Changing gateways, licensing or application paths without that comparison can introduce further faults.