}
protected void btnSend_Click(object sender, EventArgs e)
{
    MailMessage mm = new MailMessage("sender@gmail.com", "receiver@gmail.com");
    mm.Subject = txtSubject.Text;
    mm.Body = "Name: " + txtName.Text + "<br /><br />Email: " + txtEmail.Text + "<br />" + txtBody.Text;
    if (FileUpload1.HasFile)
    {
        string FileName = System.IO.Path.GetFileName(FileUpload1.PostedFile.FileName);
        mm.Attachments.Add(new Attachment(FileUpload1.PostedFile.InputStream, FileName));
    }
    mm.IsBodyHtml = true;
    SmtpClient smtp = new SmtpClient();
    smtp.Host = "smtp.gmail.com";
    smtp.EnableSsl = true;
    System.Net.NetworkCredential NetworkCred = new System.Net.NetworkCredential();
    NetworkCred.UserName = "heba@e-tarabut.com";
    NetworkCred.Password = "hebhebheb91";
    smtp.UseDefaultCredentials = true;
    smtp.Credentials = NetworkCred;
    smtp.Port = 587;
    smtp.Send(mm);
    lblMessage.Text = "Email Sent SucessFully.";
}