Do i need to authenticate when using my mail server

Question

I am trying to send an email using my mail server who i have an account with. When i run the code it returns a connection timed out and could not connect to SMTP host. Do i need to specify my username or password if so how do i do this.
This is my code Thanks in advance
import javax.mail.*;
import javax.mail.internet.*;
import java.util.*;
public class PostMail{
public static void postMail( String subject, String message , String from) throws MessagingException
     String recipients[ ] = {"[email protected]"};
boolean debug = false;
//Set the host smtp address
Properties props = new Properties();
props.put("mail.smtp.host", "mail.btopenworld.com");
// create some properties and get the default Session
Session session = Session.getDefaultInstance(props, null);
session.setDebug(debug);
// create a message
Message msg = new MimeMessage(session);
// set the from and to address
InternetAddress addressFrom = new InternetAddress(from);
msg.setFrom(addressFrom);
InternetAddress[] addressTo = new InternetAddress[recipients.length];
for (int i = 0; i < recipients.length; i++)
addressTo[i] = new InternetAddress(recipients);
msg.setRecipients(Message.RecipientType.TO, addressTo);
// Optional : You can also set your custom headers in the Email if you Want
msg.addHeader("MyHeaderName", "myHeaderValue");
// Setting the Subject and Content Type
msg.setSubject(subject);
msg.setContent(message, "text/plain");
Transport.send(msg);
public static void main(String[] arsg) throws Exception{
     postMail( "Test", "Test", "[email protected]");
     System.out.println("Done");
     System.exit(1);

Answer 1

It depends on your mail server. Most mailservers dont expect you to authenticate while a few do. First, try to telnet to your mail server using the telnet utility.
telnet <mailserver address> <smtp port - 25>
220 blah blah blah...
HELO <your name - dont mind give anything here>
250 blah blah blah....
MAIL FROM <your address>
250 Sender Ok....
RCPT TO <your friend's address>
250 Recipient Ok....
RSET
250 Reset Complete...
QUIT
221 Server closing connection....
If this is not what happens, then your mailserver requires authentication and I dont know how to do it. But from what seems to be the problem, I think you are not able to contact the mail server itself. When you do telnet to mailserver just see how long it takes to connect.