Question

I’m using the following basic code:

System.Net.Mail.MailMessage msg = new System.Net.Mail.MailMessage();

msg.to.add("[e-mail]");
msg.to.add("[e-mail]");
msg.to.add("[e-mail]");

msg.From = new MailAddress("[e-mail]", "myDomain", System.Text.Encoding.UTF8);
msg.Subject = "subject";
msg.SubjectEncoding = System.Text.Encoding.UTF8;
msg.Body = "body";
msg.BodyEncoding = System.Text.Encoding.UTF8;
msg.IsBodyHtml = false;

//Add the Creddentials
SmtpClient client = new SmtpClient();
client.Host = "192.168.0.24"; 
client.Credentials = new System.Net.NetworkCredential("[e-mail]", "password");
client.Port = 25;

try
{
   client.Send(msg);
}
catch (System.Net.Mail.SmtpException ex)
{
    sw.WriteLine(string.Format("ERROR MAIL: {0}. Inner exception: {1}", ex.Message,  ex.InnerException.Message));
}

Problem is the mail is only sent to the address in my domain ([e-mail]) and I get the following exception for the 2 other addresses:

System.Net.Mail.SmtpFailedRecipientException: Mailbox unavailable. The server response was: No such domain at this location

I suspect it’s something to do with something blocking my smtp client but not sure how to approach this.
Any idea? thanks!

Answer 1

Ron is correct,just use the 587 port and it will work as u wish.

Check this code and see if it works:

using System;
using System.Windows.Forms;
using System.Net.Mail;

namespace WindowsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            try
            {
                MailMessage mail = new MailMessage();
                SmtpClient SmtpServer = new SmtpClient("smtp.gmail.com");

                mail.From = new MailAddress("[e-mail]");
                mail.To.Add("[e-mail]");
                mail.Subject = "Test Mail";
                mail.Body = "This is for testing SMTP mail from GMAIL";

                SmtpServer.Port = 587;
                SmtpServer.Credentials = new System.Net.NetworkCredential("username", "password");
                SmtpServer.EnableSsl = true;

                SmtpServer.Send(mail);
                MessageBox.Show("mail Send");
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.ToString());
            }
        }
    }
}