diff --git a/network_gui.c b/network_gui.c
--- a/network_gui.c
+++ b/network_gui.c
@@ -1,5 +1,6 @@
 #include "stdafx.h"
 #include "ttd.h"
+#include "strings.h"
 #include "network.h"
 #include "saveload.h"