Index: /trunk/src/VBox/Devices/Serial/DrvTCP.cpp
===================================================================
--- /trunk/src/VBox/Devices/Serial/DrvTCP.cpp	(revision 59904)
+++ /trunk/src/VBox/Devices/Serial/DrvTCP.cpp	(revision 59905)
@@ -349,4 +349,18 @@
     PDRVTCP pThis = PDMINS_2_DATA(pDrvIns, PDRVTCP);
     PDMDRV_CHECK_VERSIONS_RETURN(pDrvIns);
+
+#ifdef RT_OS_WINDOWS
+    {
+        WSADATA wsaData;
+        int err;
+
+        err = WSAStartup(MAKEWORD(2,2), &wsaData);
+        if (err != 0)
+        {
+            LogRel(("DrvTCP: Failed to initialize Winsock, error %d\n", err));
+            /* XXX: let socket creation fail below */
+        }
+    }
+#endif
 
     /*