Hi Guys,
I have a Postfix server behind a gateway firewall that does content
filtering (SpamD on pfSense) and greylisting and we have an
application server that uses Postfix as its MTA, the problem is after
the initial 451 response the latter quits and send an Undeliverable
Mail to sender, what changes needs to be done on the latter in order
for it to resend email successfully, I don't have a problem with other
third party mail server except for this one. Since I don't have access
to the latter I can't provide any logs except for the following:
---
This is the Postfix program at host mail.latter.sample.
I'm sorry to have to inform you that the message returned
below could not be delivered to one or more destinations.
For further assistance, please send mail to <postmaster>
If you do so, please include this problem report. You can
delete your own text from the message returned below.
The Postfix program
<us...@former.sample>: host webmail.former.sample[210.21x.xx.xx] said:
451 Temporary failure, please try again later. (in reply to DATA command)
----
TIA.
