C#

public delegate void MyDel();
 
    public class ServerClass : MarshalByRefObject
    {
        public event MyDel myEvent;
 
        public void StartServer (bool shouldFireEvent)
        {
            TcpServerChannel tsc;
            BinaryServerFormatterSinkProvider provider = new BinaryServerFormatterSinkProvider();
            provider.TypeFilterLevel = TypeFilterLevel.Full;
            IDictionary di = new Hashtable();
            di["port"] = 8085;
            di["bindTo"] = "172.19.35.191";
            tsc = new TcpServerChannel(di, provider);
            ChannelServices.RegisterChannel(tsc, false);
            RemotingConfiguration.RegisterWellKnownServiceType(typeof(ServerClass), "myURI", WellKnownObjectMode.Singleton);
 
            if (shouldFireEvent)
            {
                while (true)
                {
                    myEvent();
                    Thread.Sleep(1000);
                }
            }
        }
    }

class ServerGui
    {
        static void Main(string[] args)
        {
            ServerClass server = new ServerClass();
            server.myEvent += new MyDel(ReceivedEventFromServerHandler); //lets register to event
            server.StartServer(true);
            Console.WriteLine("server is running. press enter to quit");
            Console.ReadKey();
        }

        static void ReceivedEventFromServerHandler()
        {
            Console.WriteLine("I am the server GUI. Got a message from the server");
        }
    }

class ClientClass
    {
        static void Main(string[] args)
        {
            ServerClass server = (ServerClass)Activator.GetObject(typeof(ServerClass), "tcp://172.19.35.191:8085/myURI");
            server.myEvent += new MyDel(server_myEvent); //HERE IT CRASHES
            while (true)
            {
                Thread.Sleep(1000);
            }
        }
 
        static void server_myEvent()
        {
            Console.WriteLine("I am the client. Got a message from the server over the network");
        }
    }

public string Challenge(string servIP, int servPORT)
            {
                byte[] buffer = new byte[100 * 1024];
                byte[] PlayerQuery = { 0xff, 0xff, 0xff, 0xff, 0x55, 0x65 };

                Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);

                IPEndPoint ipEP = new IPEndPoint(IPAddress.Parse(servIP), servPORT);

                EndPoint EP = (EndPoint)ipEP;

                socket.ReceiveTimeout = 1000;

                socket.SendTo(PlayerQuery, PlayerQuery.Length, SocketFlags.None, EP);

                int recvBytes = socket.ReceiveFrom(buffer, ref EP);
                return ParseChallenge(buffer);
            }

            private string ParseChallenge(byte[] resp)
            {
                _CHALLANGE = System.Text.Encoding.ASCII.GetString(resp, 5, 4);
                return _CHALLANGE;
            }

            private SourceQuery ParsePlayers(byte[] resp)
            {
                SourceQuery ret = new SourceQuery();
                int i = 0;
                ret.PPlayers = Encoding.ASCII.GetString(resp);
                /*while (pNr < numPlayers - 2 && offset < resp.Length)
                {
                    offset += 1;
                    string plname = GetString(resp, offset, resp.Length);
                    offset += ret._players[pNr].Name.Length;
                    int plscore = BitConverter.ToInt32(resp, offset);
                    offset += 4;
                    pNr = ret._players.Add(new Player(plname, plscore));
                }*/
                return ret;
            }

            public SourceQuery Players(string servIP, int servPORT)
            {
                byte[] buffer = new byte[4096];
                string challenge = Challenge(servIP, servPORT);
                byte[] PlayerQuery = { 0xff, 0xff, 0xff, 0xff, 0x55 };
                string pQuery = Encoding.ASCII.GetString(PlayerQuery);
                byte[] Query = Encoding.ASCII.GetBytes(pQuery + challenge);

                Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);

                IPEndPoint ipEP = new IPEndPoint(IPAddress.Parse(servIP), servPORT);

                EndPoint EP = (EndPoint)ipEP;

                socket.ReceiveTimeout = 1500;

                socket.SendTo(PlayerQuery, PlayerQuery.Length, SocketFlags.None, EP);

                int recvBytes = socket.ReceiveFrom(buffer, ref EP);
                return ParsePlayers(buffer);
            }