We are sending emails from a Group address to external clients. We include a list-unsubscribe header with options for recipient's mail client to use browser or send an email to unsubscribe. It appears that when Apple Mail users select the Unsubscribe option at the top of the email, the Unsubscribe email that is generated is undeliverable to Group members, as the Apple Mail client (when going directly through Apple and not a company email server) is adding a header Auto-Submitted: auto-replied. Google is then rejecting the email to the group address as it does with auto-responses. The same logic of auto-responses should probably not be applied to "Unsubscribe" emails. But is there something we are missing here?
Log shows: "Message looks like an auto-response and has been dropped"
A few thoughts:
1) Groups is an all-but-abandoned product from Google. They haven’t touched it in years. So I wouldn’t expect it to be fixed from Google’s end. But you could open a support ticket if you wanted to try. See https://support.google.com/a/answer/1047213?hl=en for how.
2) You could try reporting this to Apple, see https://developer.apple.com/bug-reporting/, but inter-vendor bugs of this sort often just result in finger pointing.
3) Tools like MailChimp and Constant Contact are far better than Groups for customer communications.
Hope that helps,
Ian