static string Main(string[] args)
{
    //IPAddress ipAddress = System.Net.IPAddress.Loopback;
    IPAddress ipAddress = IPAddress.Parse("192.168.0.100");
    IPEndPoint localEndPoint = new IPEndPoint(ipAddress, 1515);
    Socket sock = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
    Connect(localEndPoint, sock);
    string packet;
    packet = Console.ReadLine();
    packet += "<EOF>";
    Send(sock, packet);
    Receive(sock);
    return packet;
    //connectDone.WaitOne();
}

Esta é a seção de email do cliente, quando eu tento retornar minha string do meu servidor responder (variável de pacote) o erro do compilador éProgram '...\clie.exe' does not contain a static 'Main' method suitable for an entry point