How to get the status of sent mail in asp.net c#?

Hi sir,
Tell me the steps to get the status of sent mail in asp.net c#. Kindly give me the solution for this problem. I attached
the code below for further details.



[Hint: If i sent mail to one email id, i want to get the status of sent email]


Default.aspx.cs:
*************************

protected void Button1_Click(object sender, EventArgs e)
{
try
{
string fromEmail = ConfigurationManager.AppSettings["Email"].ToString();
string toEmail = txt_toaddress.Text;
MailMessage message = new MailMessage(fromEmail, toEmail);
message.Subject = txt_subject.Text;
message.IsBodyHtml = true;
message.Body = txt_message.Text;

SmtpClient smtp = new SmtpClient();
smtp.Send(message);




}
catch (Exception ex)
{
Response.Write(ex.Message.ToString());
}
}

With regards,
J.Prabu.
[Email:prbspark@gmail.com]