Jim said:
<snip>
I suspect this might be my final post on the topic.
This morning I sent off using Outlook 2010 an email to 110 fake email
addresses plus one good hotmail address, one good Yahoo .co.uk address and
one bad yahoo.com address via my paid-for Virgin Media account (which is
managed by Google).
I got two replies: from Mailer -daemon 1) Your message did not reach some
or all of the intended recipients and 2) This user doesn't have a yahoo.com
account.
The genuine mails to yahoo and hotmail, both got through.
So you got results that you expected. You sent to invalid e-mail
address and got the status back that your e-mail couldn't be delivered.
You specified a couple valid e-mail address and those got delivered.
What was it that you expected to happen? Is it that Virgin's operation
worked as expected but some other e-mail provider was "flaky"?
When ISPs contract out their e-mail service to another provider, like to
Yahoo or Gmail, they can also negotiate variances in that service from
the default features in an "outside" account. You may encounter
different anti-abuse quotas in the Virgin-contracted Gmail account then
you would with the open or free Gmail accounts you obtain yourself.
When you send 1 message with N recipients to the SMTP server, you're
only sending 1 message, not N copies of it, to the server. The client
aggregates all recipients in the To, Cc, and Bcc *fields* in its record
of the e-mail and sends a RCPT TO command to the server for each of
those recipients. It then follows with just 1 DATA command with the
content of the message (client-added headers and message body). So the
server gets N RCPT-TO commands followed by 1 DATA command. It then
proceeds to send out a copy of that message to the N recipients.
You get one status back, if any (since no failures means no returned
status) for the entire mail transaction. When sending to a dozen
recipients, your server doesn't report back failed statuses for a few of
them. It reports back one status. So out of a dozen recipients, say 3
of them are non-deliverable (no such user at the domain, domain doesn't
exist, target mail server remain busy too long, some rejection issued by
the target server which rejects e-mails from your sending server, etc).
You don't get back 3 NDRs. You get back one which may be a generic
error to cover any number of failures or just the NDR for the first one
that failed. You never get to see the SMTP logs of the session your
sending server had with every receiving server for your mail transaction
so you may not be able to tell what exactly failed when you specify
multiple recipients.
If you don't want to go the mailing list route to establish
communications with your group (either 1-way for newsletters or
multi-way for discussions), why not change from sending 1 message to N
recipients to sending N messages with each going to just 1 recipient.
If you have the MS Office suite then you can use MailMerge in Outlook to
send N messages to N recipients in a list. Else, use a client that is
specifically designed as a bulk mailer. The caveat here is that many
e-mail providers, especially free ones, have a maximum messages per X
minutes anti-abuse quota. That is, you can only send so many messages
within some number of minutes. You have to wait until that interval
elapses to send some more messages. Some bulk mailers have the option
of slicing up a mailing list and delaying each chunk by a specified
number of minutes to avoid the max-messages-per-X-minutes anti-abuse
quota. They can also specify how many max messages to send within a
chunk since some e-mail providers also have a max-messages-per-minute
anti-abuse quota. MailMerge has no such throttling to avoid anti-abuse
quotas. With MailMerge, it generates N copies of a message for the N
recipients, dumps them all in the Outbox folder, and Outlook obediently
sends them all in the next mail session.
So if you don't want to use a server-side mailing list solution, get a
bulk mailing client. I'm not expert in that area but remember Sue
Moshers's (an MVP) site listed some but that list might be out of date.
Look at the bulk or mass mailers listed at
http://www.slipstick.com/utilities/. An online search or searching
common download sites (download.com and softpedia.com) might find some
that meet your criteria, and some might also be free. Some are add-ons
and can work with Outlook, like use the contacts defined therein.
You could try MailMerge with Outlook (and the mailing list in Excel) but
you might end up hitting the anti-abuse quotas at whomever you're using
as the e-mail provider. However, you'll know exactly which e-mails
failed to get sent (if you don't get nailed by the max-messages-per-
minute anti-abuse quota) because you'll get a separate NDR for each
failed message. Since you're sending them out individually, the one
status you get back from the server for the mail transaction will be for
the one message you sent at a time.
