Based on what you described, you are using HBC and in this case it will work with AMT 6.2 and newer, while with older, that doesn't support HBC, it will trigger the PKI provisioning. that is the reason of this error message that you are getting.
In order to find the root cause, can you check these items:
- If you are using a internal certificate, you must inject the root CA thumbprint into ME (manually or using a USB key using USBFile.exe tool);
- Issue a certificate for vPro provisioning to Intel SCS server and add it to security context of user running the RCSServer service.
- PKI provisioning method, need that you have DHCP (doesn't work with static IP) with option 15 (suffix DNS) that matches your certificate domain.
Let us know if you have these requirements in order that we can provide a better support assistance.