David Potter asked,
| I am interested in setting up a subscription probe for the Majordomo
| lists we host. I think I saw a reference to this recently but it appears
| to have escaped my 'Inbox'.
| I think the reference was to VE.P...?
VERP, variable envelope return path; you send out each copy of the probe
with a different envelope sender that you can identify with the addressee.
John Levine just posted a good explanation.
| I originally thought I'd conjure one up using a shell script.... placing
| a unique identifier in a X-Probe: header but if some sites are not
| returning all headers maybe the Subject: is more reliable...?
You have to look at the bounces you're receiving and see what information
from the original message is being returned in them. THAT's where you have
to put the identifying information. Recently on the list-moderators list
there was a problem where a subscriber was forwarding to something that
returned only the subject and nothing else from the original message, but
many other mystery bounces have not returned the subject. There is no
single best place to identify the recipient of the probe.