There a quite a few types of messages from the forum that are system generated, such as membership accepted notifications and so on. Generally these will have a noreply@jackrail.space address. So, replying will just bounce. I can see a lot of this in the error logs.
It’s just the same as any noreply email from a company. So as to avoid disappointment and frustration, have a look at the sender address. No need to reply to the noreply mails.
Again. Discourse is a web forum, not a mailing list (that’s only a bonus extra feature), and it is a big, rich system, and makes all sorts of automated notifications. Many here use it as a pure mailing list, and so may not be used to this aspect of behaviour, since traditional mailing lists tend not to make any notifications automatically generated. So this is the explanation why you may be seeing bounced emails.
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