title: smtpException was unhandled by user code
body: <p>here is the code.</p>
  
  <pre><code>void sendMail()
  {
      MailMessage mail = new MailMessage();
  
      mail.To.Add("abc@gmail.com");
      mail.From = new MailAddress("abc@gmail.com", txt_name.Text);
      mail.Subject = txt_subject.Text;
      mail.Body = txt_body.Text;
  
      SmtpClient smtp = new SmtpClient("smtp.gmail.com");
      smtp.EnableSsl = true;
  
      NetworkCredential yetki = new NetworkCredential("abc@gmail.com", "11111111");
      smtp.Credentials = yetki;
  
      smtp.Send(mail);
  
      Response.Write("mailiniz başarılı bir şekilde gönderilmiştir");
  }
  
  protected void btn_gonder_Click(object sender, EventArgs e)
  {
      sendMail();
  }
  </code></pre>