How to fix 'Could not convert socket to TLS' error in java

Question

I was using the JavaMail API to send an email containing a text file. This code I wrote was working perfectly fine last week, however I logged on today and ran the program and received the error in the image I've attached at the bottom. I updated to the newest version of java 8 and still receive this error. (I have to use java 8 for the project for work) I looked at the java 8 patch notes for this update and saw the removed of root CA Certificates and I'm not sure what to think/do. I am posting this question because I cannot find any solution in the other tons of questions about this.

I am running Java 8 (jre 1.8.0_221) and previously was running jre 1.8.0_211. I do not know what changed as it stopped working today with v.211 and is also not working after I updated to the most recent version of Java 8 with v.221. I have tried various other properties with no success. I'm not sure if it is the Java removal of something specific (which I doubt) or if it has to do with firewall permissions any smtp permissions I may or may not have. Anyways, the code is below for the email sending portion and the code fails at Transport.send(message); with error "Could not convert socket to TLS"

                Properties props = new Properties();
                props.put("mail.smtp.auth", "true");
                props.put("mail.smtp.starttls.enable", "true");
                props.put("mail.smtp.host", host);
                props.put("mail.smtp.port", "25");
                props.put("mail.smtp.debug", "true");

                Session session = Session.getInstance(props, new javax.mail.Authenticator() {
                    protected PasswordAuthentication getPasswordAuthentication() {
                        return new PasswordAuthentication(smtpUsername, u2);
                    }
                });

                try {
                    Message message = new MimeMessage(session);
                    message.setFrom(new InternetAddress(from));
                    message.setRecipients(Message.RecipientType.TO, InternetAddress.parse(to));
                    message.setSubject(prop.getProperty("Message"));

                    BodyPart messageBodyPart = new MimeBodyPart();
                    messageBodyPart.setText(prop.getProperty("Message"));

                    Multipart multipart = new MimeMultipart();
                    multipart.addBodyPart(messageBodyPart);

                    messageBodyPart = new MimeBodyPart();
                    DataSource source = new FileDataSource(prop.getProperty("text") + ".txt");
                    messageBodyPart.setDataHandler(new DataHandler(source));
                    messageBodyPart.setFileName(prop.getProperty("filename"));
                    multipart.addBodyPart(messageBodyPart);

                    message.setContent(multipart);

                    Transport.send(message);
                    System.out.println("Sent successfully.\n");

Error Message I am receiving. Hopefully I have explained thoroughly enough. This is only my second question I've asked on here. Any help is appreciated, thanks.

Answer 1

I am not an expert , but...

You may be impacted by intentional distrusting of some root certificates in April 2019, or whenever they were applied in your environment (re: https://blogs.oracle.com/java-platform-group/jdk-distrusting-symantec-tls-certificates ).