Çözüldü C# Mail Gönderme.

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.IO;
using System.Net;
using System.Net.Mail;
namespace WindowsFormsApplication73
{
    public partial class Form1 : Form
    {   
        int sinir = 10;
        bool kontrol = true;
        public Form1()
        {
            InitializeComponent();
        }

        private **** Form1_Load(object sender, EventArgs e)
        {
            timer1.Enabled = true;
        }

        private **** timer1_Tick(object sender, EventArgs e)
        {
        baslangic:;
            FileInfo info = new FileInfo(@"C:\Users\Dosya@hotmail\Desktop\Deneme.txt");

            if (File.Exists(@"C:\Users\Dosya@hotmail\Desktop\Deneme.txt"))
            {
               
                if(info.Length>=sinir)
                {
                    mail_gonder();
                }
                
            }
            else
            {
                StreamWriter Olustur = new StreamWriter(@"C:\Users\Dosyal@hotmail\Desktop\Deneme.txt");
                Olustur.Write("");
                Olustur.Close();
                goto baslangic;
            }
            timer1.Enabled = false;
        }
        **** mail_gonder()
        {
            MailMessage msj = new MailMessage();
            msj.From = new MailAddress("[email protected]");
            msj.To.Add("[email protected]");
            string konu = "asd", icerik = "Deneme";
            msj.Attachments.Add(new Attachment(@"C:\Users\Dosyal@hotmail\Desktop\Deneme.txt"));
            msj.Subject = konu;
            msj.Body = icerik;
            SmtpClient smtp = new SmtpClient();
            smtp.Credentials = new System.Net.NetworkCredential("Epostam", "Şifrem");
            smtp.Port = 587;
            smtp.Host = "smtp.live.com";
            smtp.EnableSsl = true;
            
            try
            {
                smtp.Send(msj);
            }
            catch (Exception)
            {
                kontrol = false;
            }
            timer1.Enabled = false;
            timer2.Enabled = true;

        }
        private **** timer2_Tick(object sender, EventArgs e)
        {
            if(kontrol == true)
            {
                StreamWriter TkrOlustur = new StreamWriter(@"C:\Users\Dosya\Desktop\Deneme.txt");
                TkrOlustur.Write("Tekrar");
                TkrOlustur.Close(); 
            }
            timer1.Enabled = true;
            timer2.Enabled = false;
        }
    }
}