The mailing list for listmasters using Sympa

[<address@concealed>]

Hi,

I am a user on a sympa 5.3.4 mailing list.    I am using the web interface for
most everything.    When I click reply to a post, the subject will be Re: the-
topic , and I can write my message.    I can send it.  But then when I look at
the Archive,  even though my message has the same Subject line, it's not
included in the thread.   It's like I started a new thread.

Do I have to do something manually to keep my reply within the same thread of
conversation?  It's strange.    What is the software precisely looking for to
keep a single thread?

Thanks,
Sam