HTML content with images and links blocked

Question

Hello,
I very much need some help here because my company needs to send out newsletters to our clients in HTML format soon and so far the email with HTML content is being blocked as spam while text content works fine. Specifically, whenever I add a link or an image in HTML content, the email doesn't go through. I tried sending in multipart format but it is also not sending HTML with images and links. Here is my attempt:
                                props.setProperty("mail.transport.protocol", "smtp");
                                 props.setProperty("mail.host", "mail.server.com");
                                 props.setProperty("mail.user", "joeuser");
                                 Session mailSession = Session.getDefaultInstance(props, null);
                                 mailSession.setDebug(true);
                                 Transport transport = mailSession.getTransport();
                                 MimeMultipart mp = new MimeMultipart("alternative");
                                 MimeBodyPart htmlPart = new MimeBodyPart();
                                 MimeBodyPart textPart = new MimeBodyPart();
                                 textPart.setText("Just to make it multipart");
                                 htmlPart.setHeader("MIME-Version", "1.0");
                                 htmlPart.setHeader("Content-Type", htmlPart.getContentType());
                                 htmlPart.setContent(strHtmlMessage, "text/html");
                                 mp.addBodyPart(textPart);
                                 mp.addBodyPart(htmlPart);
                                 MimeMessage message = new MimeMessage(mailSession);
                                 message.setHeader("MIME-Version", "1.0");
                                 message.setHeader("Content-Type", mp.getContentType());
                                 message.setHeader("X-Mailer", "Recommend-It Mailer V2.03c02");
                                 message.setContent(mp);
                                 message.setSubject(strSubject);
                                 message.setFrom(new InternetAddress("[email protected]"));
                                 message.addRecipient(Message.RecipientType.TO,
                                         new InternetAddress("[email protected]"));
                                         transport.connect();
                                         transport.sendMessage(message,
                                         message.getRecipients(Message.RecipientType.TO));
                                 transport.close();This code is one of my numerous attempts to make HTML send images and links. Please, let me know if there is a workaround way to make JavaMail send HTML with links and images in the message body. Your help will be greatly appreciated.

Answer 1

The JavaMail FAQ has information on creating HTML messages, including
messages with both plain text and HTML. Did you find it?
BTW, your code has many unnecessary statements, such as setting
the Mime-Version header, which JavaMail will do for you, and setting
the Content-Type header, which JavaMail does as a side-effect of the
setContent or setText calls.
Other than that, it looks like your code should be correctly creating a
multipart/alternative message. If the recipient is still rejecting it you
need to figure out what it is about the message that makes the recipient
think it's spam. Can you send a similar message using another mailer?
Can you send the message to a different recipient?