diff --git a/src/gaiageo/gg_shape.c b/src/gaiageo/gg_shape.c
index ee2f1cf..01f2571 100644
--- a/src/gaiageo/gg_shape.c
+++ b/src/gaiageo/gg_shape.c
@@ -58,7 +58,7 @@ the terms of any one of the MPL, the GPL or the LGPL.
 #endif
 
 #ifdef _WIN32
-#include <Windows.h>
+#include <windows.h>
 #endif
 
 #if OMIT_ICONV == 0		/* if ICONV is disabled no SHP support is available */