Hi there!
This is Tochi Ezebube with the Active Directory Certificate Services (ADCS) engineering team; I wanted to share some further details on how to write a custom policy module for the ADCS Network Device Enrollment Service (NDES) in Windows Server 2012 R2 and onwards.
Here it is: how-to-write-an-ndes-policy-module.
And here’s some general info on policy modules in NDES.
Let me know if you have any questions!
Tochi