diff --git a/src/gui/qt/mainwindow/mainwindowimpl.cpp b/src/gui/qt/mainwindow/mainwindowimpl.cpp
index a62045bd..6205c9a2 100755
--- a/src/gui/qt/mainwindow/mainwindowimpl.cpp
+++ b/src/gui/qt/mainwindow/mainwindowimpl.cpp
@@ -2335,6 +2335,11 @@ void mainWindowImpl::networkError(int errorID, int osErrorID) {
 				tr("Could not connect to the server."),
 				QMessageBox::Close); }
 		break;
+		case ERR_SOCK_CONNECT_TIMEOUT:
+			{ QMessageBox::warning(this, tr("Network Error"),
+				tr("Connection timed out.\nPlease check the server address.\n\nIf the server is behind a NAT-Router, make sure port forwarding has been set up on server side."),
+				QMessageBox::Close); }
+		break;
 		case ERR_SOCK_SELECT_FAILED:
 			{ QMessageBox::warning(this, tr("Network Error"),
 				tr("Internal network error: \"select\" failed."),
diff --git a/src/net/clientstate.h b/src/net/clientstate.h
index 01050dd5..b3e4b18b 100644
--- a/src/net/clientstate.h
+++ b/src/net/clientstate.h
@@ -21,8 +21,10 @@
 #ifndef _CLIENTSTATE_H_
 #define _CLIENTSTATE_H_
 
+#include <net/socket_helper.h> // needed for correct order of header files.
 #include <string>
 #include <memory>
+#include <core/boost/timer.hpp>
 
 #define CLIENT_INITIAL_STATE ClientStateInit
 
@@ -110,6 +112,8 @@ public:
 
 	virtual ~ClientStateStartConnect();
 
+	void SetTimer(boost::microsec_timer timer);
+
 	// Call connect.
 	virtual int Process(ClientThread &client);
 
@@ -128,6 +132,8 @@ public:
 
 	virtual ~ClientStateConnecting();
 
+	void SetTimer(const boost::microsec_timer &timer);
+
 	// "Poll" for the completion of the TCP/IP connect call.
 	virtual int Process(ClientThread &client);
 
@@ -135,6 +141,10 @@ protected:
 
 	// Protected constructor - this is a singleton.
 	ClientStateConnecting();
+
+private:
+
+	boost::microsec_timer m_connectTimer;
 };
 
 // State: Session init.
diff --git a/src/net/common/clientstate.cpp b/src/net/common/clientstate.cpp
index 01c4d496..d6576620 100644
--- a/src/net/common/clientstate.cpp
+++ b/src/net/common/clientstate.cpp
@@ -34,6 +34,7 @@
 using namespace std;
 
 #define CLIENT_WAIT_TIMEOUT_MSEC	50
+#define CLIENT_CONNECT_TIMEOUT_SEC	10
 
 
 ClientState::~ClientState()
@@ -240,6 +241,9 @@ ClientStateStartConnect::Process(ClientThread &client)
 		int errCode = SOCKET_ERRNO();
 		if (errCode == SOCKET_ERR_WOULDBLOCK)
 		{
+			boost::microsec_timer connectTimer;
+			connectTimer.start();
+			ClientStateConnecting::Instance().SetTimer(connectTimer);
 			client.SetState(ClientStateConnecting::Instance());
 			retVal = MSG_SOCK_INTERNAL_PENDING;
 		}
@@ -267,6 +271,12 @@ ClientStateConnecting::~ClientStateConnecting()
 {
 }
 
+void
+ClientStateConnecting::SetTimer(const boost::microsec_timer &timer)
+{
+	m_connectTimer = timer;
+}
+
 int
 ClientStateConnecting::Process(ClientThread &client)
 {
@@ -295,7 +305,12 @@ ClientStateConnecting::Process(ClientThread &client)
 		retVal = MSG_SOCK_CONNECT_DONE;
 	}
 	else if (selectResult == 0) // timeout
-		retVal = MSG_SOCK_INTERNAL_PENDING;
+	{
+		if (m_connectTimer.elapsed().seconds() >= CLIENT_CONNECT_TIMEOUT_SEC)
+			throw ClientException(ERR_SOCK_CONNECT_TIMEOUT, 0);
+		else
+			retVal = MSG_SOCK_INTERNAL_PENDING;
+	}
 	else
 		throw ClientException(ERR_SOCK_SELECT_FAILED, SOCKET_ERRNO());
 
diff --git a/src/net/socket_msg.h b/src/net/socket_msg.h
index 2a719028..13d57c52 100644
--- a/src/net/socket_msg.h
+++ b/src/net/socket_msg.h
@@ -32,13 +32,14 @@
 #define ERR_SOCK_LISTEN_FAILED			9
 #define ERR_SOCK_ACCEPT_FAILED			10
 #define ERR_SOCK_CONNECT_FAILED			11
-#define ERR_SOCK_SELECT_FAILED			12
-#define ERR_SOCK_RECV_FAILED			13
-#define ERR_SOCK_SEND_FAILED			14
-#define ERR_SOCK_CONN_RESET				15
-#define ERR_SOCK_CONN_EXISTS			16
-#define ERR_SOCK_INVALID_PACKET			17
-#define ERR_SOCK_INVALID_STATE			18
+#define ERR_SOCK_CONNECT_TIMEOUT		12
+#define ERR_SOCK_SELECT_FAILED			13
+#define ERR_SOCK_RECV_FAILED			14
+#define ERR_SOCK_SEND_FAILED			15
+#define ERR_SOCK_CONN_RESET				16
+#define ERR_SOCK_CONN_EXISTS			17
+#define ERR_SOCK_INVALID_PACKET			18
+#define ERR_SOCK_INVALID_STATE			19
 // The following errors are game errors.
 #define ERR_NET_VERSION_NOT_SUPPORTED	101
 #define ERR_NET_SERVER_FULL				102