Fail to Connect to NetworkServer

It looks easy but I cannot figure out why I cannot connect to my server in local.

Simple Server Code:

    void Start() {
        if (NetworkServer.Listen(15937)) {
            Debug.Log("Server Created!");
            NetworkServer.RegisterHandler(MsgType.Connect, OnConnected);
        } else {
            Debug.Log("Failed To Create Server!");
        }
    }

    void OnConnected(NetworkMessage netMsg) {
        Debug.Log("Client connected");
    }

Simple Client Code:

    void Start () {
        client = new NetworkClient();
        client.Connect("127.0.0.1", 15937);
    }

    void Update () {
        if (client.isConnected) {
            Debug.Log("Connected to server!");
        } else {
            Debug.Log("Failed to Connected to server!");
        }
    }

PS: I get a message saying :

NetworkManager detected a script reload in the editor. This has caused the network to be shut down.
UnityEngine.Networking.NetworkIdentity:UNetStaticUpdate()

I am not sure if it causes the problem or not. Can someone lead me to the solution?

If you have any scripts that’s derived (extends) from NetworkManager, you should remove Awake method from that and put your initialization in Start or OnStartClient.

See this thread for more information.