Sending Failure

Question

When I try to send email, I got the following exception,
javax.mail.SendFailedException: Sending failed;
nested exception is:
class javax.mail.SendFailedException: Invalid Addresses;
nested exception is:
class javax.mail.SendFailedException: 550 <[email protected]>... Relaying denied
here is the code for my program,
public void sendMsg(String to[]){
try {
Properties props = System.getProperties();
props.put("mail.smtp.host", mailhost);
// Get a Session object
Session session = Session.getDefaultInstance(props, null);
// construct the message
Message msg = new MimeMessage(session);
if (from != null)
     msg.setFrom(new InternetAddress(from));
else
     msg.setFrom();
Address toAddress = new InternetAddress("[email protected]");
//msg.setRecipients(Message.RecipientType.TO, InternetAddress.parse(to1, false));
msg.addRecipient(Message.RecipientType.TO, toAddress);
InternetAddress[] addressTo = new InternetAddress[to.length];
for (int i = 0; i < to.length; i++)
addressTo[i] = new InternetAddress(to);
msg.setRecipients(Message.RecipientType.TO, addressTo);
if (cc != null)
     msg.setRecipients(Message.RecipientType.CC, InternetAddress.parse(cc, false));
if (bcc != null)
     msg.setRecipients(Message.RecipientType.BCC,     InternetAddress.parse(bcc, false));
msg.setSubject(subject);
msg.setContent(content, "text/plain");
msg.setHeader("X-Mailer", mailer);
msg.setSentDate(new Date());
// send the message
Transport transport = session.getTransport("smtp");
//transport.connect(mailhost, "", "");
transport.send(msg);
//transport.sendMessage(msg, msg.getAllRecipients());
transport.close();
System.out.println("Mail was sent successfully.");
catch (Exception e) {
     e.printStackTrace();
Can anyone tell me is it due to the invalid address or it cannot relay?
thanks

Answer 1

Hi,
relaying deny does occur while MTA(mail server) send your email
to the target site. some mail server would check some condition
to decide if it has to deal with your request. For exmaple,
your ip is not in its service list, spamming email, or some
thing else. The case may vary and depends on the configuration
of the mail server.
good luck,
Alfred Wu