diff --git a/src/machine.cpp b/src/machine.cpp
index 395413e660..8555878c41 100644
--- a/src/machine.cpp
+++ b/src/machine.cpp
@@ -21,7 +21,7 @@
 
 #if defined(PLATFORM_WINDOWS)
 #  define WIN32_LEAN_AND_MEAN
-#  include <Windows.h>
+#  include <windows.h>
 #endif
 
 using namespace vm;