Email Notification option in Asp.net

private void Mail_sen()
    {
        try
        {
            string bBody = mailmsg();

            string email = TextBox4.Text;
            string sSub = "Contact_Us";
            SendMailmsg(bBody, email, email, email, sSub, "sendcc");
            //lblerror.Text = "Mail Sent Successfully.";
            //lblerror.ForeColor = Color.Green;
        }
        catch (Exception ex)
        {
            //lblerror.Text = "Send Email Failed.";
            //lblerror.ForeColor = Color.Red;
        }
    }

 private string mailmsg()
    {
        StringBuilder strHTML = new StringBuilder();
        strHTML.Append("<table width="70%">");
        strHTML.Append("<tr><td width="100%" colspan="2"><b>Dear  abc </b></td></tr>");

        strHTML.Append("<tr bgcolor="cayn"><center><table><tbody><tr><td width="100%" colspan="2">CONTACT </td></tr></tbody></table></center></tr>");
        strHTML.Append("<tr><td width="20%"><b>Name : </b></td><td width="80%">abc</td></tr>");
        strHTML.Append("<tr><td width="20%"><b>Email ID : </b></td><td width="80%">abc@gmail.com</td></tr>");
        strHTML.Append("<tr><td width="20%"><b>Phone No : </b></td><td width="80%">999999999</td></tr>");
        strHTML.Append("<tr><td width="20%"><b>Comments : </b></td><td width="80%">hi this code try</td></tr>");

        strHTML.Append("</table>");
        return strHTML.ToString();
    }

        public static string SendMailmsg(string body, string msgto, string cc, string msgfrom, string sub, string cond)
    {
        string status = "fail";
        try
        {
            System.Net.Mail.MailMessage message = new System.Net.Mail.MailMessage();
            message.Body = body;
            message.IsBodyHtml = true;
            if (cond == "notsendcc")
            {
                message.To.Add(msgto);
            }

            if (cond == "sendcc")
            {
                message.To.Add(msgto);
                message.CC.Add(cc);
            }
            message.From = new System.Net.Mail.MailAddress(msgfrom);
            message.Subject = sub;
            // message.ReplyTo = new MailAddress(repto.Trim());
            message.Priority = System.Net.Mail.MailPriority.High;
            SmtpClient SmtpMail = new SmtpClient();
            {
                SmtpMail.Host = "smtp.gmail.com";
                SmtpMail.Port = 587;
                //SmtpMail.Port = 25;
              //  SmtpMail.EnableSsl = false;
  SmtpMail.EnableSsl = true;
                SmtpMail.UseDefaultCredentials = true;
                SmtpMail.DeliveryMethod = System.Net.Mail.SmtpDeliveryMethod.Network;
                SmtpMail.Credentials = new System.Net.NetworkCredential("email_id", "pass******");
                SmtpMail.Send(message);
            }
            message = null;
            status = "success";
        }
        catch (Exception ex)
        {
            throw (ex);
        }
        return status;
    }