Am 04.06.2012 15:36, schrieb Ed W:
I think you know about the MailASail business. We run small ISP selling mail accounts to customers. *our customers* want to voluntarily tell senders when they have downloaded an email via POP. The basic requirement is when the message is accessed via POP, then the sender (presumably defined by the FROM address) is sent a notification.
this isnt what you asked in the subject
"Can we know when a user read our email?"
the best and true answer: "never"
---snip
as long all senders and users are on the same mailsystem/storage you might wrote i.e some watch daemon on your smtp mailsystem with if mail in storage with "Disposition-Notification-To" from "your sender" grepped by sasl header "Authenticated sender:" has gone from new to cur in "your recipients" storage maildir and subfolders
you may also try use complex smtp transport header_checks combis with i.e /(^Disposition-Notification-To:.*)/ REPLACE X-$1 to mark mail etc
and/or policy servers , milters etc perhaps with writings in dbs and comparing verbose dovecot logs etc
cause there are uni ways to setup smtp and dovecot servers you must find your way fitting your setup
as i said , i see only small relates to dovecot cause the only header which is standard in mail clients is Message Disposition Notification, so the sender has to use it anyway and you have to filter this mails by it additional only for "your senders" and "your recipients" then you have to find a way checking status of this mails in "your storage"
if you allready have amavis included, you might code it there somehow
or look at
policy server for ideas who you might goal
another way.....
perhaps you might include a sieve global filter rule with filtering Disposition-Notification-To only from "your sender domains" and doing a simple mail notify action about it was delivered, or using some no official sieve plugins for actions with external binaries ( procmail etc )
-- Best Regards
MfG Robert Schetterer
Germany/Munich/Bavaria