How to solve: Sending the email to the following server failed SocketException: Permission denied: connect

Question

I am facing issue while sending mails programmatically using Java. I confirmed from the network team that sending mails through Java is blocked using firewall. but am able to get the response from telnet in my windows command prompt. Please find the details below.

Code used to send mail using Javax Mail:

public static void main(String[] args) throws MessagingException {
        String host = "mailhost.xxx";
        String to = "[email protected]";
        String from = "[email protected]";
        String subject = "test";
        String messageText = "body test";

        Properties props = System.getProperties();
        props.put("mail.host", host);
        props.put("mail.transport.protocol", "smtp");
        props.put("mail.smtp.port", "25");

        // If using authentication, otherwise comment out
        props.put("mail.smtp.auth", "true");

        // Gmail requires TLS, your server may not
        props.put("mail.smtp.starttls.enable", "true");

        // Session mailSession = Session.getDefaultInstance(props, null);

        Session mailSession = Session.getInstance(props, new javax.mail.Authenticator() {
            @Override
            protected PasswordAuthentication getPasswordAuthentication() {
                return new PasswordAuthentication("username", "password");
            }
        });

        Message msg = new MimeMessage(mailSession);
        msg.setFrom(new InternetAddress(from));
        InternetAddress[] address = { new InternetAddress(to) };
        msg.setRecipients(Message.RecipientType.TO, address);
        msg.setSubject(subject);
        msg.setSentDate(new Date());
        msg.setText(messageText);

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

        // connect with authentication
        // transport.connect(host,"myUsername" , "myPassword");

        // connect without authentication
        transport.connect();
        transport.sendMessage(msg, address);

        transport.close();

        System.out.println("Mail was sent to " + to);
        System.out.println(" from " + from);
        System.out.println(" using host " + host + ".");

    }

Using Telnet am able to send mails in command prompt: telnet mailhost.xxx 25 am getting the response like:

220 mailhost Microsoft ESMTP MAIL Service ready at Tue, 29 Mar 201
6 23:34:36 -0700

After googling I also tried setting JVM argument in Eclipse as below, no luck still getting the exception as shown below

-Djava.net.preferIPv4Stack=true

Exception:

Exception in thread "main" org.apache.commons.mail.EmailException: Sending the email to the following server failed : mailhost.xxx:25
    at org.apache.commons.mail.Email.sendMimeMessage(Email.java:1242)
    at org.apache.commons.mail.Email.send(Email.java:1267)
    at edu.xxx.pageobject.appcenter.util.ReportGenerator.main(ReportGenerator.java:328)
Caused by: javax.mail.MessagingException: Could not connect to SMTP host: mailhost xxx, port: 25;
  nested exception is:
    java.net.SocketException: Permission denied: connect
    at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1282)
    at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:370)
    at javax.mail.Service.connect(Service.java:297)
    at javax.mail.Service.connect(Service.java:156)
    at javax.mail.Service.connect(Service.java:105)
    at javax.mail.Transport.send0(Transport.java:168)
    at javax.mail.Transport.send(Transport.java:98)
    at org.apache.commons.mail.Email.sendMimeMessage(Email.java:1232)
    ... 2 more
Caused by: java.net.SocketException: Permission denied: connect
    at java.net.TwoStacksPlainSocketImpl.socketConnect(Native Method)
    at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:339)
    at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:200)
    at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:182)
    at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172)
    at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
    at java.net.Socket.connect(Socket.java:579)
    at java.net.Socket.connect(Socket.java:528)
    at com.sun.mail.util.SocketFetcher.createSocket(SocketFetcher.java:232)
    at com.sun.mail.util.SocketFetcher.getSocket(SocketFetcher.java:189)
    at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1250)
    ... 9 more

Let me know any possible solution to resolve the above issue.

Answer 1

Posting an alternate solution for my above issue: As we were using Exchange accounts we were able to send the mails programmatically using EWS (Exchange Web Services) API. EWS Getting Started Guide Link