Overview
Windows Server 2022 servers running build 20348.5622 may experience Remote Desktop Services (RDS) issues after installing the September 8, 2026 cumulative update KB5122882.
Possible symptoms include:
- RDP connections hang or fail.
- Existing RDP sessions cannot disconnect or log off.
- New RDP connections become unresponsive.
- The server may become slow or unresponsive.
- MMC, File Explorer, RDS Licensing Diagnoser, or Windows Update may also hang.
The issue may occur several hours after installing the update or after users log off from RDP sessions.
Affected Servers
This issue may affect:
- Windows Server 2022 Dedicated Servers
- Windows Server 2022 Virtualizor VPS
- Windows Server 2022 servers running build 20348.5622
- Servers where KB5122882 has been installed
Affected Update
KB5122882
Windows Server 2022 September 8, 2026 cumulative update
Affected build: 20348.5622
Recommended Fix
Microsoft released KB5129237, an out-of-band cumulative update for Windows Server 2022.
KB5129237 updates the server to build 20348.5631 and addresses the RDS issue.
KB5129237 can be installed directly over the affected build. A rollback of KB5122882 is not required.
Customer Action Required
As the server is self-managed, Windows Update and Windows OS patching activities must be performed by the customer.
Before proceeding, please ensure that:
- A valid backup of the server/data is available.
- A suitable maintenance window is scheduled.
- Console access is available in case RDP becomes unavailable.
For Virtualizor VPS servers, customers can use the available VPS console/VNC access through the Virtualizor panel if RDP is unavailable.
For Dedicated Servers, customers should use the available remote console/out-of-band management such as iDRAC, iLO, or another available console.
Step 1 – Check the Current Windows Build
Log in to the Windows Server and run:
winver
Alternatively, open PowerShell as Administrator and run:
Get-ComputerInfo -Property OsBuildNumber, OsVersion
If the server is running build:
20348.5622
the server is affected and should be updated.
Step 2 – Download KB5129237
Download KB5129237 from the Microsoft Update Catalog:
https://www.catalog.update.microsoft.com
Search for:
KB5129237
Download the appropriate Windows Server 2022 x64 .msu package corresponding to build 20348.5631.
Step 3 – Copy the Update to the Server
Copy the downloaded .msu file to the Windows Server.
For example:
C:\Windows\Temp\
If RDP is not working, use the available console/VNC access instead of repeatedly attempting RDP connections.
For Virtualizor VPS:
Use the VPS console/VNC available through the Virtualizor panel.
For Dedicated Servers:
Use the available remote/out-of-band console such as iDRAC, iLO, or another available console.
Step 4 – Install KB5129237
Open Command Prompt or PowerShell as Administrator and run:
wusa.exe C:\Windows\Temp\windows10.0-kb5129237-x64.msu
Alternatively, the update can be installed silently using:
wusa.exe C:\Windows\Temp\windows10.0-kb5129237-x64.msu /quiet /norestart
It is recommended to install the update while the server is responsive and before further RDP session logoffs trigger the issue.
Step 5 – Restart the Server
A restart is required to complete the installation.
Run:
shutdown /r /t 0
Important:
The restart will cause temporary server downtime. Please perform this activity during a suitable maintenance window.
The update includes servicing stack changes, and the restart may take longer than usual. Do not manually power off or interrupt the server during the update/reboot process.
Step 6 – Verify the Update
After the server comes back online, verify the Windows build.
Run:
Get-ComputerInfo -Property OsBuildNumber, OsVersion
or:
winver
Expected build:
20348.5631
If the server still shows:
20348.5622
the update has not been successfully applied. Please check the Windows CBS logs for installation errors before retrying the update.
CBS log location:
C:\Windows\Logs\CBS\CBS.log
Step 7 – Test Remote Desktop
After confirming that the server is running build 20348.5631:
1. Test a new RDP connection.
2. Confirm that you can log in successfully.
3. Log off the RDP session.
4. Test another RDP connection.
5. Confirm that RDP sessions can disconnect and log off normally.
Important Notes
- KB5122882 is the affected September 2026 update.
- Affected build: 20348.5622.
- KB5129237 is the corrective out-of-band cumulative update.
- Expected fixed build: 20348.5631.
- A server restart is required.
- The update activity will cause temporary server downtime.
- If RDP is unavailable, use the Virtualizor console/VNC for VPS servers or iLO/iDRAC/remote console for Dedicated Servers.
- KB5129237 is available through the Microsoft Update Catalog.
Microsoft KB5129237:
Affected Update KB5122882:
Microsoft Update Catalog:
https://www.catalog.update.microsoft.com
Support Scope
This is a self-managed server activity.
The customer is responsible for:
- Downloading the Microsoft update.
- Installing KB5129237.
- Scheduling the required downtime.
- Rebooting the server.
- Verifying the Windows build.
- Troubleshooting any Windows Update installation errors.
Our team provides the VPS/Dedicated Server infrastructure and console access. Windows OS patching, Windows Update, and OS-level configuration on self-managed servers must be performed by the customer.