Re: [Sonic #5605759] outgoing emails are getting lost/dropped

[http://dummy.us.eu.org/robert (Robert )]

 > From: Sonic Support <http://www.sonic.net/~support>
 > Date: Mon, 10 Jun 2019 10:27:14 -0700
 >
 > Hello Robert,
 > 
 > If those reports are from our SMTP server, we passed the mail on. What email 
 > address are you getting these errors on?

You mean, the recipient address?  It varies.  In this case, it was to
http://dummy.us.eu.org/noelleg .  At other times, it has been
http://dummy.us.eu.org/noelleg .

It's possible that there have been other addresses, but I haven't heard
about complaints about lost email to other addresses.

 > When mail doesn't get delivered, is it 
 > always to the same recipient or different addresses?

It seems like just two email addresses: http://dummy.us.eu.org/noelleg and
http://dummy.us.eu.org/noelleg .  Again, it's possible that this problem has affected
another addresses, but I haven't heard about any lost messages so far.
Since I have the most visibility into http://dummy.us.eu.org/noelleg and
http://dummy.us.eu.org/noelleg, those are the ones I have been focusing on.

In the case of http://dummy.us.eu.org/noelleg, that lands in a gmail.com
Inbox.  I can look at that Inbox and see that the message was never
received.  (I don't have the same level of visibility into
http://dummy.us.eu.org/noelleg except for the fact that the email was never received at
all, not even in the graymail.)

 > Please let us know so we can look in to this more for you.

Not sure if it matters, but this set-up has been working for many, many
years without a problem.  It's only within the last 6 months or so that
this problem has cropped up.

The most annoying parts are:
 (1) it says that each message was delivered successfully, and
 (2) the dropped emails seem random and, so, it is not consistently
     reproducible.

 > Thank you,