I have a Discourse setup, 1.6.6, stock install. Email functionality is working perfectly, except signup emails.
When I try to create a new test user in incognito mode, the email is not sent. If I try to click “Send Activation Email” as admin, it’s the same, nothing sent.
It’s not even visible in /admin/email/sent, or in skipped or bounced or rejected list. It simply disappears.
I had the same problem 2 weeks ago, digest email and email notifications working fine, but invite emails not received by users nor visible in Admin > Email > Sent. And no error showing in the Error Log.
Did not find where it came from, but it resolved with an upgrade to Discourse 1.7.0 beta7+27…