Sending email with username by comparing email in database

See more:

C#

ASP.NET

email

i have a page where users login , i also have forgot username link which sends users their username via email. I am using an outlook account to test which is open. i check the email address against one in my database table for users and send email to user if the address is present in db table. i am getting the following error '

Quote:

An exception of type 'System.Net.Mail.SmtpFailedRecipientException' occurred in App_Web_2woqyecp.dll but was not handled in user code

'

Quote:

Additional information: Mailbox unavailable. The server response was: 5.7.1 Unable to relay

and if i user another email address not from the outlook the email is not sent but i dont get an error

What I have tried:

public void forgot()
    {
        string username = "";

        SqlConnection con = new SqlConnection(strConnString);
        SqlCommand cmd = new SqlCommand(spgetuser, con);
        cmd.Parameters.AddWithValue("@email", txtEmailP.Text);

        con.Open();
        using (SqlDataReader dr = cmd.ExecuteReader())
        {

            if (dr.Read())
            {

                username= dr["username"].ToString();

            }

        }
        con.Close();


        if (!string.IsNullOrEmpty(username))
        {
            try
            {
                string emailFrom = "me@example.com";

                string body = "<div style='border: medium solid grey; width: 500px; height: 266px;font-family: arial,sans-serif; font-size: 17px;'>";
                body += "<h3 margin-top:0px;'>Username Recovery</h3>";
                body += "<br />";
                body += ("Your Username is: " + username);
                body += "<br />";
                body += "<br />";
                body += "Kinds Regards";
                body += "<br />";
                body += "</div>";

                System.Net.Mail.MailMessage message = new System.Net.Mail.MailMessage();
                //message.To.Add(emailTo);
                //message.Subject = subject;
                message.From = new System.Net.Mail.MailAddress(emailFrom);
                message.IsBodyHtml = true;
                message.Body = body;
                message.Priority = System.Net.Mail.MailPriority.High;
                message.Subject = "username Recovery";

                message.From = new System.Net.Mail.MailAddress(emailFrom);


                SmtpClient SmtpMail = new SmtpClient();
                SmtpMail.EnableSsl = true;
                SmtpMail.Port = 25;
                SmtpMail.Host = "myhost";
               
                System.Net.ServicePointManager.ServerCertificateValidationCallback = delegate(object s,
                          System.Security.Cryptography.X509Certificates.X509Certificate certificate,
                          System.Security.Cryptography.X509Certificates.X509Chain chain,
                          System.Net.Security.SslPolicyErrors sslPolicyErrors)
                {
                    return true;
                };

                // compare session username to username in database
                SqlCommand command = new SqlCommand(spcheck,con)
                command.Parameters.AddWithValue("@email", txtEmailP.Text);

                using (SqlConnection connection =
                           new SqlConnection(strConnString))
                {

                    connection.Open();

                    command.Connection = connection;

                    SqlDataReader reader = command.ExecuteReader();

                    // Call Read before accessing data.
                    while (reader.Read())
                    {

                        var to = new MailAddress(reader["Email"].ToString());
                        message.To.Add(to);

                    }

                    // Passing values to smtp object        
                    SmtpMail.Send(message);

                    ScriptManager.RegisterStartupScript(this, typeof(string), "Msg","alert('request has been sent');", true);


                    Response.Redirect("~/lgn.aspx");

                    // Call Close when done reading.
                    reader.Close();
                }



            }

                

            catch (Exception ex)
            {
                throw ex;
            }


        }
    }


    protected void Button1_Click(object sender, EventArgs e)
    {

        this.forgot();
    }