c# socket通信的有关问题

c# socket通信的问题
，我的服务端在运行，并且与客户端通信，但是还有的客户端连不上.
服务端关键代码：
 private void socketbind()
        {
            try
            {
                string ip = pxl.serverip;
                IPAddress ipadd = IPAddress.Parse(ip);
                IPEndPoint iep = new IPEndPoint(ipadd, pxl.serverport);
                ssk = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
                ssk.Bind(iep);
                ssk.Listen(10);
                //AcceptConnection();
                log.Info("服务已启动!");
                thread = new Thread(AcceptConnection);
                thread.IsBackground = true;
                thread.Start();
            }
            catch (Exception ex)
            {
                log.Error(ex.ToString());
            }
        }

void AcceptConnection()
        {
            Socket msgsok = null;
            while (true)
            {
                try
                {
                    msgsok = ssk.Accept();
                    log.Info(msgsok.RemoteEndPoint.ToString() + "已经连接！");
                    NetworkStream ns = new NetworkStream(msgsok);
                    try
                    {
                        #region //接收用户标识的长度，最多3位，最大值999
                        byte[] bt = new byte[3];
                        log.Info("接收身份信息！");
                        try
                        {
                            ns.Read(bt, 0, bt.Length);
                        }
                        catch
                        {
                            log.Info(msgsok.RemoteEndPoint.ToString()+"发生异常，关闭连接并释放资源！");
                            closeConnection(msgsok, ns);
                            continue;
                        }