Hi Gemabli,
Thanks for your post. Before moving on, please understand that Terrafom is a third-party software. If we encountered some issue with Terrafom, it is highly recommended that we contact the Terrafom support at first. Here is the support channel: Support - Terraform Enterprise | Terraform | HashiCorp Developer
Also, based on my research, please confirm that you have open the port Windows RDP : 3389 TCP as Terraform on Windows Server 2016 uses this port number to create the virtual machine.
Best Regards,
Ian Xue
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