I writed only one line :
HDEVINFO Handle = SetupDiGetClassDevs(NULL,NULL,NULL,DIGCF_ALLCLASSES);
But
Handle = 0xfff...
GetlastError = 127 means "The specified procedure could not be found."
I can't reproduce your issue and your code works for me. I test on Raspberry Pi 3 with Windows 10 IoT Core version 17763.1.
The code I used in a Windows IoT Core Console Application and debug follow this tutorial:
#include <windows.h>
#include <setupapi.h>
int main(int argc, char **argv)
{
HDEVINFO Handle = SetupDiGetClassDevs(NULL, NULL, NULL, DIGCF_ALLCLASSES);
DWORD errCode = GetLastError();
}
You can have a try to see if it works.
I upload my project here.