I was asked by a colleague to help him with a problem he had customizing a Windows Server 2019 deployment. He had no problem customizing a Window Server 2016 VM so had no idea what the problem was.

The first thing I did was a manual deployment. I created a VM and created a VM customization specification. And in the end, I had a fully functional VM which was customized. So it worked without any issues.

But the deployment through Microsoft Orchestrator did not work. The VM was created but was never customized. So for some reason, the automated deployment is not working and the manual deployment is.

The biggest difference is the use of PowerCLI. On the runbook servers, the installed PowerCLI version was 6.5. Quite old and not compatible with vCenter 6.7.

So my suggestion was to update PowerCLI to the latest and greatest version. And after that, the customization worked!

Conclusion: always check your compatibility!