diff --git a/src/autorun.cc b/src/autorun.cc
index 1384296..2b49822 100644
--- a/src/autorun.cc
+++ b/src/autorun.cc
@@ -1,8 +1,14 @@
 #include "autorun.h"
 
+#ifdef _WIN32
+#define WIN32_LEAN_AND_MEAN
+#define NOMINMAX
+#include <windows.h>
+#endif
+
 #ifdef _WIN32
 // 0x530010
-HANDLE gInterplayGenericAutorunMutex;
+static HANDLE gInterplayGenericAutorunMutex;
 #endif
 
 // 0x4139C0
diff --git a/src/autorun.h b/src/autorun.h
index 438af79..c479849 100644
--- a/src/autorun.h
+++ b/src/autorun.h
@@ -1,14 +1,6 @@
 #ifndef AUTORUN_H
 #define AUTORUN_H
 
-#ifdef _WIN32
-#define WIN32_LEAN_AND_MEAN
-#define NOMINMAX
-#include <windows.h>
-
-extern HANDLE gInterplayGenericAutorunMutex;
-#endif
-
 bool autorunMutexCreate();
 void autorunMutexClose();