How to read mail using SMTP from C #?

I have to read an inbox (Inbox Outlook Microsoft Exchange) of an email, I have the email account, the password and by the mail server I have the host (the email is configured as SMTP NOT POP3 or IMAP ) and the port.

This is my code

private void connection()
    {   
        try
        {

            using (ImapClient client = new ImapClient("smtp.miempresa.com", 25, "[email protected]", "mipasswaor", AuthMethod.Login, false))
            {

                if (client.Supports("IDLE") == false)
                {
                    MessageBox.Show("El servidor no soporta IMAP IDLE");
                }
                client.NewMessage += new EventHandler<IdleMessageEventArgs>(OnNewMessage);


            }
        }
        catch (System.Exception ex)
        {
            MessageBox.Show("Error no controlado:\n"+ex.Message,"Error");
        }

    }
    static void OnNewMessage(object sender, IdleMessageEventArgs e)
    {
        MessageBox.Show("Mensaje nuevo recibido");
        MailMessage m = e.Client.GetMessage(e.MessageUID, FetchOptions.Normal);
        f.Invoke((MethodInvoker)delegate
        {
            f.richTextBox1.AppendText("From: " +m.From + "\n"+
                                        "Subject: " +m.Subject+"\n"+
                                         "Body: "+ m.Body+"\n"+
                                         "Attach: "+m.Attachments+"\n");
        });
    }

With this code, what I want is to show in a RichTextBox the emails in the tray, but when I try to connect it produces the following error:

  

220 SMT-KMCI2004.mycompany.com Microsoft ESMTP MAIL Service ready at   Wed, 5 Sep 2018 14:40:40 -0400

Any idea of the error, or any other way of reading Microsoft Exchange emails?