I am migrating an unmanaged C++ application from a windowed GUI app to a NT Service.
If there is a change in the display resolution, it sends some information to some specialized hardware.

From a Windows App, I just trap WM_DISPLAYCHANGE and deal with it there.

But for a NT Service, I cannot find a way to get to that message.
The SERVICE_CONTROL_... messages don't seem to cover these types of events.