diff --git a/Engine/source/main/main.cpp b/Engine/source/main/main.cpp
index b5fea8a07..ad3556913 100644
--- a/Engine/source/main/main.cpp
+++ b/Engine/source/main/main.cpp
@@ -283,9 +283,11 @@ int main(int argc, const char **argv)
 #include "app/mainLoop.h"
 #include "T3D/gameFunctions.h"
 
-#if defined(WIN32) || defined(_WIN32) //tell switchable graphics supported systems that they need to use the beefier GPU
-extern "C" { __declspec(dllexport) unsigned long NvOptimusEnablement = 0x00000001; }
-extern "C" { __declspec(dllexport) unsigned long AmdPowerXpressRequestHighPerformance = 0x00000001; }
+#if defined(WIN32) || defined(_WIN32) 
+//tell switchable graphics supported systems that they need to use the beefier GPU
+#include <windows.h>
+extern "C" { __declspec(dllexport) DWORD NvOptimusEnablement = 0x00000001; }
+extern "C" { __declspec(dllexport) DWORD AmdPowerXpressRequestHighPerformance = 0x00000001; }
 #else 
 extern "C" { int NvOptimusEnablement = 1; }
 extern "C" { int AmdPowerXpressRequestHighPerformance = 1; }