Difficulty sending mail to secure SMTP, SMTPAddressFailedException: 554

Question

I keep getting the following exception in my application:
class com.sun.mail.smtp.SMTPAddressFailedException: 554 <[email protected]>: Recipient address rejected: Relay access denied
My code is as follows:
public class SMTPSender {
     private Session session;
     public SMTPSender() {
          Properties props = new Properties();
          props.setProperty("mail.smtp.host", AutomailingUtility.HOST);
          props.put("mail.smtps.auth", AutomailingUtility.AUTH);
          props.put("mail.smtp.port", "465");
          props.put("mail.smtp.socketFactory.port", "465");
          props.put("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory");
          props.put("mail.smtp.socketFactory.fallback", "false");
          Authenticator auth = new MyAuthenticator(AutomailingUtility.USERNAME, AutomailingUtility.PASSWORD);
          session = Session.getInstance(props, auth);
     public void sendMessage(String toUser, String message, String subject) {
          try {
               Message msg = new MimeMessage(session);
               msg.setSubject(subject);
               msg.setSentDate(new Date());
               InternetAddress ia = new InternetAddress(AutomailingUtility.FROM_ADDRESS);
               msg.setFrom(ia);
               msg.setRecipients(Message.RecipientType.TO, InternetAddress.parse(toUser + "@mail.gatech.edu"));
               msg.setText(message);
               Transport.send(msg);
          } catch (AddressException e) {
               e.printStackTrace();
          } catch (MessagingException e) {
               e.printStackTrace();
}All the Automailing constants are strings.
I'd appreciate the help

Answer 1

The code? For regular SMTP with authentication I believe you needprops.put("mail.smtp.auth", "true");whereas you set up the mail.smtps.auth property instead. However I don't have any experience with secure SMTP, so I don't know what's right in that case. Are those other applications you mention using secure SMTP or just regular SMTP?