Error in sending email through SMTP

Question

I'm trying to send an email through Java Code using gmail as the SMTP. But getting an exception as below. Can you pls let me know why is it not able to find the gmail host. I'm working in office network, not sure if some firewall is stopping it from sending. If yes, what is the way out ?

Exception in thread "main" com.sun.mail.util.MailConnectException: Couldn't connect to host, port: smtp.gmail.com, 586; timeout -1;
  nested exception is:
    java.net.UnknownHostException: smtp.gmail.com
    at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:2053)
    at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:697)
    at javax.mail.Service.connect(Service.java:364)
    at javax.mail.Service.connect(Service.java:245)
    at mail.JavaEmail.sendEmail(JavaEmail.java:72)
    at mail.JavaEmail.main(JavaEmail.java:22)
Caused by: java.net.UnknownHostException: smtp.gmail.com

Java Source Code :

package mail;

import java.util.Properties;

import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.AddressException;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;

public class JavaEmail
{
    Session mailSession;

    public static void main(String args[]) throws AddressException,    MessagingException
    {
        JavaEmail javaEmail = new JavaEmail();
        javaEmail.setMailServerProperties();
        javaEmail.draftEmailMessage();
        javaEmail.sendEmail();
    }

    private void setMailServerProperties()
    {
        Properties emailProperties = System.getProperties();
        emailProperties.put("mail.smtp.port", "586");
        emailProperties.put("mail.smtp.auth", "true");
        emailProperties.put("mail.smtp.starttls.enable", "true");
        mailSession = Session.getDefaultInstance(emailProperties, null);
    }

    private MimeMessage draftEmailMessage() throws AddressException, MessagingException
    {
        String[] toEmails = { "to-mail@gmail.com" };
        String emailSubject = "Test email subject";
        String emailBody = "This is an email sent by JAVA Code";
        MimeMessage emailMessage = new MimeMessage(mailSession);
        /**
         * Set the mail recipients
         * */
        for (int i = 0; i < toEmails.length; i++)
        {
            emailMessage.addRecipient(Message.RecipientType.TO, new InternetAddress(toEmails[i]));
        }
        emailMessage.setSubject(emailSubject);
        /**
         * If sending HTML mail
         * */
        emailMessage.setContent(emailBody, "text/html");
        /**
         * If sending only text mail
         * */
        //emailMessage.setText(emailBody);// for a text email
        return emailMessage;
    }

    private void sendEmail() throws AddressException, MessagingException
    {
        /**
         * Sender's credentials
         * */
    String fromUser = "from-user@gmail.com";
        String fromUserEmailPassword = "*****";

        String emailHost = "smtp.gmail.com";
        Transport transport = mailSession.getTransport("smtp");
        transport.connect(emailHost, fromUser, fromUserEmailPassword);
        /**
         * Draft the message
         * */
        MimeMessage emailMessage = draftEmailMessage();
        /**
         * Send the mail
         * */
        transport.sendMessage(emailMessage, emailMessage.getAllRecipients());
        transport.close();
        System.out.println("Email sent successfully.");
    }
}

Answer 1

You're connecting to the wrong port. Google's SMTP server for TLS is 587. You can see more information on this here: http://email.about.com/od/accessinggmail/f/Gmail_SMTP_Settings.htm

Answer 2

this may help you

Properties props = new Properties();   
        props.setProperty("mail.transport.protocol", "smtp");   
        props.setProperty("mail.host", mailhost);   
        props.put("mail.smtp.auth", "true");   
        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");   
        props.setProperty("mail.smtp.quitwait", "false");   

        session = Session.getDefaultInstance(props, this);

Answer 3

The following code may help you to solve your problem, its working........

import java.util.*;
import javax.mail.*;
import javax.mail.internet.*;

public class Email {

private static String USER_NAME = "username";  // GMail user name (just the part before "@gmail.com")
private static String PASSWORD = "password"; // GMail password

private static String RECIPIENT = "xxxxx@gmail.com";

public static void main(String[] args) {
String from = USER_NAME;
String pass = PASSWORD;
String[] to = { RECIPIENT }; // list of recipient email addresses
String subject = "Java send mail example";
String body = "hi ....,!";

sendFromGMail(from, pass, to, subject, body);
}

private static void sendFromGMail(String from, String pass, String[] to, String subject, String body) {
Properties props = System.getProperties();
String host = "smtp.gmail.com";

props.put("mail.smtp.starttls.enable", "true");

props.put("mail.smtp.ssl.trust", host);
props.put("mail.smtp.user", from);
props.put("mail.smtp.password", pass);
props.put("mail.smtp.port", "587");
props.put("mail.smtp.auth", "true");


Session session = Session.getDefaultInstance(props);
MimeMessage message = new MimeMessage(session);

try {


    message.setFrom(new InternetAddress(from));
    InternetAddress[] toAddress = new InternetAddress[to.length];

    // To get the array of addresses
    for( int i = 0; i < to.length; i++ ) {
        toAddress[i] = new InternetAddress(to[i]);
    }

    for( int i = 0; i < toAddress.length; i++) {
        message.addRecipient(Message.RecipientType.TO, toAddress[i]);
    }



    message.setSubject(subject);
    message.setText(body);


    Transport transport = session.getTransport("smtp");


    transport.connect(host, from, pass);
    transport.sendMessage(message, message.getAllRecipients());
    transport.close();

}
catch (AddressException ae) {
    ae.printStackTrace();
}
catch (MessagingException me) {
    me.printStackTrace();
  }
 }
} 

Answer 4

I had same issue. Changed host smtp.gmail.com to ip 74.125.133.109 and now it works well.