How to fix error 426 in SCVMM

What should the netstat command look like if everything is working correctly? I believe that port 443 is not listening, is that normal? Also, where can I find the log files?

When the SCVMM agent is functioning correctly, you should see listening ports for TCP 443 (HTTPS) and WinRM ports 5985 (HTTP) and 5986 (HTTPS) when running netstat -ano | findstr LISTENING. These ports allow secure communication between the VMM management server and the Hyper-V host. If port 443 does not appear as listening, that can be normal depending on your configuration, but at least one of the WinRM ports (5985 or 5986) should be active.

To verify, you can also use PowerShell with Get-NetTCPConnection | Where-Object {$_.State -eq 'Listen'} to confirm which ports are open. If none of the expected ports are listening, it may indicate a firewall or service configuration issue.

For logs, the SCVMM agent writes installation and runtime logs under %ProgramData%\\VMMLogs on the Hyper-V host. Look for files such as vmmAgent.msi_date_time.log for installation details and other agent logs for communication issues. On the VMM management server, you can enable debug logging by creating a folder C:\\vmmlogs and using logman commands to capture Event Trace Logs (ETL) for deeper troubleshooting. Additionally, standard event logs under Applications and Services Logs > Microsoft > Windows > Virtual Machine Manager can provide useful error messages.

In summary, check that WinRM ports are listening via netstat or PowerShell, and review the logs in %ProgramData%\\VMMLogs and the Event Viewer for detailed error codes. This should help pinpoint why the agent is not responding.

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Jason.

Thanks for that. I now have this error :

Error (20552)

VMM does not have appropriate permissions to access the resource 'C:\Windows\system32\qmgr.dll' on the HYPERV server.

What can I do?

Error (20552) typically indicates that the VMM service account does not have sufficient permissions to access required system files on the Hyper-V host. This can happen if the account being used by SCVMM to connect does not have local administrator rights or if there are restrictions applied through group policy or security settings.

The first step is to ensure that the SCVMM service account has local administrator privileges on the Hyper-V host. You can check this by adding the account to the Administrators group on the host machine. Next, verify that the SCVMM agent is running under the correct context and that no antivirus or endpoint protection software is blocking access to system DLLs.

It is also important to confirm that the SCVMM management server and the Hyper-V host are using compatible versions of the agent and that the communication channel is not restricted by firewall rules. Reviewing the SCVMM logs under %ProgramData%\\VMMLogs on the host can provide more detail about which permissions are failing.

If the issue persists, you may need to re-register the SCVMM agent on the host by uninstalling and reinstalling it with elevated permissions. This ensures that all required DLLs and services are properly registered and accessible. In some cases, running SCVMM with elevated privileges or adjusting DCOM permissions can also resolve access issues.

Should I set / change the password of the SCVMM account?