Confusion between Reply To and Reply List in email responses

[Jonathan5]

I wrote a few posts about it here:

Confusion between Reply To and Reply List in email responses

I guess you’re right and the presence of the List-Post header understandably makes Thunderbird think it’s a mailing list email. Probably a Reply-To header would suffice. The following is from RFC 2369 - The Use of URLs as Meta-Syntax for Core Mail List Commands and their Transport through Message Header Fields 3.4. List-Post The List-Post field describes the method for posting to the list. This is typically the address of the list, but MAY be a moderator, or potentially some other form of sub…

Here is the original problem described:

Emails are not threaded in Outlook 2013

When turning on emails for every post to a forum, the emails do not thread correctly, at least in Outlook 2013. It looks like there’s an attempt to make it work, based on the In-Reply-To headers, but somehow it’s still not working :(. I imagine Outlook has some strange heuristics you might have to appease…

List-Post was blindly copied from somewhere else without any consideration being given to what it is for. It hasn’t anything to do with threading - as far as I know anyway!