Smtp username/password

Question

import java.io.*;
import java.util.*;
import javax.mail.*;
import javax.mail.internet.*;  
import javax.mail.event.*;     
import java.net.*;
import javax.activation.*;
public class sendEmail {
        public static void send(String from, String to,
                                String subject, String content)
                throws AddressException, MessagingException {
     Properties props=new Properties();
        props.put("smtp.domainName.com","domainName");
     Session   session1  =  Session.getDefaultInstance(props,null);
     Message msg =new MimeMessage(session1);
     msg.setFrom(new InternetAddress(from));
           msg.setRecipients(Message.RecipientType.TO,InternetAddress.parse(to,false));
           msg.setSubject(subject);
           msg.setContent(content,"text/html");       
           Transport.send(msg);           
}This code was working well on my dedicated server but know I am working on VPS.
My server provided said the previously it was open smtp but now there is username and password for smtp server.
Any help will be highly appreciated
The OS=CentOS Enterprise Linux 5.x
Thanks & best regards

Answer 1

public class sendEmail {
        public static void send(String from, String to,
                                String subject, String content)
                throws AddressException, MessagingException {
     Properties props=new Properties();
     Session   session  =  Session.getDefaultInstance(props,null);
     String protocol = "smtp";
         props.put("mail." + protocol + ".auth", "true");
     Transport transport = session.getTransport(protocol);
        transport.connect("[email protected]", "password");       
     Message msg =new MimeMessage(session);
     msg.setFrom(new InternetAddress(from));
           msg.setRecipients(Message.RecipientType.TO,InternetAddress.parse(to,false));
           msg.setSubject(subject);
           msg.setContent(content,"text/html");       
           transport.send(msg);           
}It throws the following error:
javax.mail.AuthenticationFailedException