diff --git a/common/network/TcpSocket.cxx b/common/network/TcpSocket.cxx
index 04e0895..7e11588 100644
--- a/common/network/TcpSocket.cxx
+++ b/common/network/TcpSocket.cxx
@@ -23,6 +23,7 @@
 #ifdef WIN32
 //#include <io.h>
 #include <winsock2.h>
+#include <ws2tcpip.h>
 #define errorNumber WSAGetLastError()
 #else
 #define errorNumber errno