I understand that Gmail groups emails together by subject for its conversation view.  I get it, I love it.I am a member of a Google Group that receives an email at the same time every day, and these are forwarded to my individual email address instantly.  The email sent to the Google Group email address is identical:  same sender, same subject, same body (from an automatic process).  When I receive these emails each day in Gmail, they are not grouped together in a single conversation, but rather fill up my inbox with individual messages.  The emails are precisely 24 hours apart, so I doubt that they aren't being grouped because of a lengthy time gap.  The email subjects don't include any Re: or Fwd:, however I've sent emails from one of my accounts to another with the exact subject used from these emails and the 3 I tested grouped together into a single conversation with 3 emails, but again, did not group to the existing email messages that came from the Google Group.Are there any other criteria for grouping that would be causing these to not get grouped together in a conversation?I've tossed two of these emails into a diff program and compared what is different.  My understanding is the subject is what matters, and that is identical though.Received:  (appears several lines, ip, SMTP id, and +addressing string are different)X-pstn-nxp (different bodyHash and headerHash)Authentication-Results (contains different +addressing string)Return-Path:  (the email back to the Google Group has a different +addressing string)Received-SPF (the email back to the Google Group has a different +addressing string)Message-IDSending myself an identical email message from one of my emails to the other, 21 hours account did not group.  So...I guess is there anything I can do to make these group into a conversation?
Gmail not grouping messages with the same subject from Google Groups
gmail;google groups