Editing List of mail server software (section)

==[[Simple Mail Transfer Protocol|SMTP]]==
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* [[agorum core]]
* [[Apache James]]
* [[Axigen]]
* Chasquid<ref>{{Cite web|url=https://blitiri.com.ar/p/chasquid/|title=SMTP server (MTA) written in Go}}</ref>
* [[Citadel/UX|Citadel]]
* [[CommuniGate Pro]]{{efn|name=n1}}
* [[Courier Mail Server|Courier]]
* [[Eudora Internet Mail Server]]
* [[Exim]]{{efn|name=n1|mentioned in Mail (MX) Server Survey 2023}}
* [[FirstClass]]
* [[Gordano Messaging Suite]]{{efn|name=n1}}
* [https://docs.halon.io/manual/ Halon Engage & Protect]
* [[Haraka (software)|Haraka]]
* [[HCL Domino]] / formerly [[IBM Lotus Domino]]
* [[hMailServer]]
* [[IceWarp Mail Server]] (formerly Merak Mail Server){{efn|name=n1}}
* [[Ipswitch IMail Server]]{{efn|name=n1}}
* [[Ironport]]
* [[Kerio Connect]]{{efn|name=n1}}
* [http://koukan-mta.net Koukan]
* [[MailEnable]]{{efn|name=n1}}
* Mailtraq
* [[MDaemon]]{{efn|name=n1}}
* [[Mercury Mail Transport System]]{{efn|name=n1}}
* [[MeTA1]]
* [[Microsoft Exchange Server]]{{efn|name=n1}}
* [[MMDF]]
* [[Novell NetMail]]
* [[OpenSMTPD]]{{efn|name=n1}}
* [[Openwave Systems]]
* [[Open-Xchange]]
* [[Oracle Beehive]]
* [[Oracle Communications Messaging Server]]
* [[Poste.io]]
* [[Postfix (software)|Postfix]]{{efn|name=n1}}
* [[PowerMTA]]
* [[qmail]]{{efn|name=n1}}
* [[qpsmtpd]]
* [[RaidenMAILD]]
* [[Scalix]]
* [[Sendmail]]{{efn|name=n1}}
* [[Smail]]
* [[SparkEngine]]
* [[Stalwart Mail Server]]
* [[Sun Java System]]
* [[Surgemail]]{{efn|name=n1}}
* [[vSMTP]]
* [[WinGate (computing)|WinGate]]
* [[WinWebMail]]{{efn|name=n1}}
* [[XMail]]{{efn|name=n1}}{{efn|name=n4|uses [[ESMTP]] protocol}}
* [[Zimbra]]
* [[ZMailer]]
}}