It seems NOT a Microsoft problem because with "Recipient Filter Agent" exchange answer "550 5.1.10 RESOLVER.ADR.RecipientNotFound; Recipient not found by SMTP address lookup" when a recipient is not found So I don't know why when postfix get "550 5.1.10 RESOLVER.ADR.RecipientNotFound; Recipient not found by SMTP address lookup" from Exchange 2016 it doesn't consider unexistant that recipient Someone can write me the answer of Exchange 2010 to a non existant recipient ?
Nicola Piazzi CED - Sistemi COMET s.p.a. Via Michelino, 105 - 40127 Bologna - Italia Tel. +39 051.6079.293 Cell. +39 328.21.73.470 Web: www.gruppocomet.it -----Messaggio originale----- Da: li...@rhsoft.net [mailto:li...@rhsoft.net] Inviato: mercoledì 7 settembre 2016 10:49 A: users@spamassassin.apache.org Oggetto: Re: postfix reject_unverified_recipient and Exchange 2016 Am 07.09.2016 um 10:42 schrieb Nicola Piazzi: > I have a problem using reject_unverified_recipient to verify under > Exchange 2016 that I don't have with Exchange 2010 how is that a spamassassin or even postfix related problem? call the microsoft support why their stuff is playing backscatter in recent versions (as you can see by all that exchange bounces flying around in the web) there is nothing the delivery software can do when exchange has no clue about it's valid rcpt's until it received and acknolwedged the full message instead just reject the rcpt workaround: list your vaild RCPT's diretly on your inboud MX and maintain it parallel to exchange > Postfix is used to send and receive mail and is between the internet > and the internal Exchange Server Now, when an internet user send an > email to our domain postfix verify it making an rcptto to our exchange > using reject_unverified_recipient instruction This worked well with > Exchange 2010 but now with Exchange 2016 doesn't work. > Exchange 2016 needs the installation of Recipient Filter Agent and > obviously I installed it. > Now we have Frontend Transport that answer at port 25 and verify > recipient at DATA phase and the Hub Transport that answer at port 2525 > and verify recipient at RCPT TO > > Here Exchange 2016 at port 25 that verify unknown recipient at DATA > phase telnet 10.1.1.126 25 > 220 GEMMA.gruppocomet.net Microsoft ESMTP MAIL Service ready helo me > 250 GEMMA.gruppocomet.net Hello [10.2.6.4] mail from:e...@ext.com > 250 2.1.0 Sender OK > rcpt to:doesntex...@gruppocomet.it > 250 2.1.5 Recipient OK > data > 354 Start mail input; end with <CRLF>.<CRLF> some data
