diff --git a/lib/py/src/ext/endian.h b/lib/py/src/ext/endian.h
index 1660cbd..a2cf594 100644
--- a/lib/py/src/ext/endian.h
+++ b/lib/py/src/ext/endian.h
@@ -25,7 +25,7 @@
 #ifndef _WIN32
 #include <netinet/in.h>
 #else
-#include <WinSock2.h>
+#include <winsock2.h>
 #pragma comment(lib, "ws2_32.lib")
 #define BIG_ENDIAN (4321)
 #define LITTLE_ENDIAN (1234)