Error 550 5.7.1 with several mail servers ?
We can't send mail on several remote SMTP server we got an 550 5.7.1 error notification:
<mail@domain>: host mail.keysourcerail.com.au[184.108.40.206]
said: 550 5.7.1 Your email messages have been blocked by the recipient OR
by Trend Micro Email Reputation Service. Contact the recipient or his/her
administrator using alternate means to resolve the issue. (in reply to RCPT
We never got this before Zimbra.
<firstname.lastname@example.org>: host mx1.free.fr[220.127.116.11] said: 554 too many errors
detected from your IP (18.104.22.168), please visit Postmaster.free.fr
(in reply to DATA command)