Dr. Wietse,
Thank you again for your time. I have been an off-and-on-again user of Postfix
for many years, and it is a real honor (and surprise!) to get support directly
from its originator.
> The hop-count limit is reached in the REMOTE mail server.
I suspected as much, but I wasn't sure. Thanks for clarifying this.
> There are two possibilities:
>
> - The failing message already has lots of Received: headers (which
> is something that you may be able to fix by removing some or all).
It doesn't because the message is being created at the server where Postfix is
installed.
> - The REMOTE mail server has an unreasonably-low hop-count limit
> (which is something that only the remote system adminstrator can
> fix).
This is the only possibility that remains... and since the system administrator
for that system is difficult to communicate with, my guess was that the single
innocent "Received:" header added by Postfix was the tipping point. For this
reason, I used the "header_checks" parameter to strip it off before sending it
to the external mail server...
...and now everything works.
Thank you very much! Your work makes a real difference.
Ahmed.
