Hello,
Thank you for the detailed error information.
Since your other servers are working fine, this points to a problem specific to this new machine's identity or its communication with the domain, rather than an issue with the WSUS server.
If the EC2 instance was created from an image that was not properly generalized (sysprep), it may have a duplicate SUSClientID as another machine on the network. WSUS requires every client to have a unique ID.
- Open PowerShell as an Administrator on the problematic server.
- Run the following commands one by one. This will stop the service, delete the registry key, restart the service, and force it to report to the WSUS server to generate a new ID.
# Stop the Windows Update Service Stop-Service -Name wuauserv # Remove the registry keys associated with the client ID. Remove-ItemProperty -Path "HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate" -Name "SusClientId" -Force -ErrorAction SilentlyContinue Remove-ItemProperty -Path "HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate" -Name "SusClientIdValidation" -Force -ErrorAction SilentlyContinue # Restart the Windows Update Service Start-Service -Name wuauserv # Force the client to check in with the WSUS server and generate a new ID UsoClient.exe StartScan - Try running your Install-WindowsUpdate command again.