In "Windows Kits\8.0\Include\um\winbase.h", there is this check:
#if (NTDDI_VERSION >= NTDDI_WIN7SP1)
It controls whether the CopyContext function is pulled in for desktop apps. The NTDDI_WIN7SP1 definition is no where to be found in the SDK. It seems to be missing from "Windows Kits\8.0\Include\shared\sdkddkver.h". Adding it as:
#define NTDDI_WIN7SP1 0x06010100
solved a problem I was having with my own definition of CopyContext in a header generated from IDL. Please fix this!
Also update http://msdn.microsoft.com/en-us/library/windows/desktop/aa383745(v=vs.85).aspx. This page also needs some work in the "Windows 7 with SP1" note regarding VS2012: http://msdn.microsoft.com/en-us/library/windows/desktop/hh134234(v=VS.85).aspx.