diff --git a/StopWatch.h b/StopWatch.h
index 3f8fa19..5ddccbd 100644
--- a/StopWatch.h
+++ b/StopWatch.h
@@ -20,6 +20,7 @@
 #define	STOPWATCH_H
 
 #if defined(_WIN32) || defined(_WIN64)
+#define _WINSOCKAPI_
 #include <windows.h>
 #else
 #include <sys/time.h>
diff --git a/TCPSocket.h b/TCPSocket.h
index f3321ed..7a20eb3 100644
--- a/TCPSocket.h
+++ b/TCPSocket.h
@@ -30,7 +30,8 @@
 #include <arpa/inet.h>
 #include <errno.h>
 #else
-#include <winsock.h>
+#include <winsock2.h>
+#include <ws2tcpip.h>
 #endif
 
 #include <string>
diff --git a/UDPSocket.h b/UDPSocket.h
index 729a7a3..ec5de9c 100644
--- a/UDPSocket.h
+++ b/UDPSocket.h
@@ -31,7 +31,8 @@
 #include <arpa/inet.h>
 #include <errno.h>
 #else
-#include <winsock.h>
+#include <winsock2.h>
+#include <ws2tcpip.h>
 #endif
 
 class CUDPSocket {