diff --git a/simgear/io/raw_socket.cxx b/simgear/io/raw_socket.cxx
index 7fe2c688..ecc8671f 100644
--- a/simgear/io/raw_socket.cxx
+++ b/simgear/io/raw_socket.cxx
@@ -39,7 +39,8 @@
 #include <errno.h>
 
 #if defined(WINSOCK)
-#  include <winsock.h>
+#  include <winsock2.h>
+#  include <ws2tcpip.h>
 #  include <stdarg.h>
 #else
 #  include <sys/types.h>