There's been a few occasions where we've had spam controls work a bit more aggressively than we'd like and ticket messages were blocked as false positives because of them. This isn't a problem in an email client because you can simply peruse your Spam folder, and while WHMCS does allow you to view the ticket mail import log, it's kind of hidden away and easily forgotten (unlike a Spam folder which is always showing in your email folder listing).
If you've ever been in a similar situation, this hook will help! It shows the 10 most recent failures to import because of spam controls at the bottom of the support ticket listing page. It also excludes mailer-daemon bounces in the event you've got those blocked to cut down on useless tickets / email loops.
Installation: Upload this file inside /includes/hooks/ directory.
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