Geoff Chappell, Software Analyst
The public symbol file NTKRPAMP.PDB for the original release of Windows 10 tells that the kernel is built with the CM_X.H header at
and draws from it the following type definition:
|46||enum _REG_NOTIFY_CLASS||line 24207 in WDM.H;
line 22172 in NTOSP.H
The header CM_X.H is not known in any Device Driver Kit (DDK) or Windows Driver Kit (WDK).