error C2440: '=' : cannot convert from 'void *' to 'NTSTATUS (__stdcall *)(HANDLE,ULONG,POBJECT_ATTRIBUTES)'

подскажите плиз в чем дело?
исходник:
#include "stdafx.h"
VOID LocateNTDLLEntryPoints()
{
if( !(NtOpenKey = (void *) GetProcAddress( GetModuleHandle("ntdll.dll"),
"NtOpenKey" )) ) {
printf("Could not find NtCreateKey entry point in NTDLL.DLL\n");
exit(1);
}
}
BOOL APIENTRY DllMain( HANDLE hModule,
DWORD ul_reason_for_call,
LPVOID lpReserved
)
{
return TRUE;
}