Un-provision Provisioned Intel vPro Machine in Enterprise Environment

How do you all un-provision provisioned machine? In lab environment, of course we can do it manually in the BIOS. How about enterprise environment? I was doing this research last week and found a tool to do it remotely. Unfortunately, this doesn’t works well. The tools prompt me an error like the picture below.



I confirmed that my machine is built with Vpro and it has been provisioned before. I have also tried to turn off the windows firewall and allow port 16992, but no luck.

Any other good method or workaround are most welcome. Thanks =)