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using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Net.Mail;

namespace MailSenden
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
           

        }

        private void Form1_Load(object sender, EventArgs e)
        {           

        }

        private void button1_Click(object sender, EventArgs e)
        {
            
            String token = (string)e.UserState;

            if (e.Cancelled)
            {
                Console.WriteLine("[{0}] Send canceled.", token);
            }
            if (e.Error != null)
            {
                Console.WriteLine("[{0}] {1}", token, e.Error.ToString());
            }
            else
            {
                Console.WriteLine("Message sent.");
            }
            mailSent = true;
        }
        public static void Main(string[] args)
        {
           
            SmtpClient client = new SmtpClient(args[0]);
            
            MailAddress from = new MailAddress("Jonah1998@hotmail.de",
               "Jane " + (char)0xD8 + " Clayton",
            System.Text.Encoding.UTF8);
            
            MailAddress to = new MailAddress("MyGamesPlay@hotmail.com");
        
            MailMessage message = new MailMessage(from, to);
            message.Body = "This is a test e-mail message sent by an application. ";
           
            string someArrows = new string(new char[] { '\u2190', '\u2191', '\u2192', '\u2193' });
            message.Body += Environment.NewLine + someArrows;
            message.BodyEncoding = System.Text.Encoding.UTF8;
            message.Subject = "test message 1" + someArrows;
            message.SubjectEncoding = System.Text.Encoding.UTF8;
           
            client.SendCompleted += new
            SendCompletedEventHandler(SendCompletedCallback);
            
            string userState = "test message1";
            client.SendAsync(message, userState);
            Console.WriteLine("Sending message... press c to cancel mail. Press any other key to exit." );
            string answer = Console.ReadLine();
          
            if (answer.StartsWith("c") && mailSent == false)
            {
                client.SendAsyncCancel();
            }
            
            message.Dispose();
            Console.WriteLine("Goodbye.");
        }
    }
}                    

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static bool mailSent = false;

private static void SendCompletedCallback(object sender, AsyncCompletedEventArgs e)
{
    // Get the unique identifier for this asynchronous operation.
    String token = (string) e.UserState;

    // ...
}                    

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 private void button1_Click(object sender, EventArgs e)
        {

            string strBetreff = textBox1.Text;
            string strNachricht = "Inhalt der Mail";
            string strNachricht1 = richTextBox1.Text;
            string strVon = "Jonah1998@hotmail.de";
            string strAn  = "Joah1998@hotmail.de";
            string strSmtpServer = "pop3.live.com";
            string strUser = "User";
            string strPasswort = "xxx";

            MailMessage mail = new MailMessage();
            MailAddress from = new MailAddress(strVon);
            mail.To.Add(strAn);
            mail.From = from;
            mail.Subject = strBetreff;            
            mail.Body = strNachricht;
            mail.Body = strNachricht1;
            string host = strSmtpServer;
            int port = 25;
            SmtpClient client = new SmtpClient(host, port);

            System.Net.NetworkCredential nc = new System.Net.NetworkCredential(strUser, strPasswort);
            client.Credentials = nc;
            client.Send(mail);