Issue: Outlook shows a red X at the bottom of HighLevel bulk emails when sent via SMTP2GO or other SMTP servers.
Cause: Your SMTP email open-tracking pixel is injected after the HTML document closes.
Evidence (last line of email source):
</div></body></html><img src="https://link.bizwisdom.com.au/v1/smtp_email/event/opened?message=..." height="1px" width="1px" style="display: none;">
This places the <img> outside <body>/<html>, causing Outlook to render a broken-image placeholder.
Expected: Inject the pixel before </body> (as occurs with Mailgun sends)
Mailgun works as expected so it is not unreasonable to expect that the same result can be achieved regardless of SMTP server used in GHL.