Kate Swap File 2.0 ed5c8977a9fb418999cc7e113c7a97d5SI$ fetchmail --sslcertckWESIESI>ESI ESIBESIiESInESIgESIoESI!ESI  ESI  ESI lESI oESI kESIsESI ESIpESIrESIoESImESIiESIsESIiESInESIgESWESINESIoESIwESI ESIsESIeESInESIdESI ESI aESI nESI  ESI eESI mESIaESIiESIlESI ESIfESIrESIoESImESI ESILESIMESIDESIEESI ESItESIoESI ESIdaemon@billhowell.caESI3,ESI4 ESI5aESI6nESI7dESI8 ESI9tESI:rESI;yESI< ESI=aESI>gESI?aESI@iESIAnESWBESWESI>ESI>ESI ESI$ fetchmail --sslcertckWIC2 messages for daemon@billhowell.ca at mail.lexi.net (7313 octets).WCI+fetchmail: Connection errors for this poll:W+IIname 0: connection to localhost:smtp [::1/25] failed: Connection refused.WIIOname 1: connection to localhost:smtp [127.0.0.1/25] failed: Connection refused.WOI+fetchmail: SMTP connect to localhost failedW+I~fetchmail: SMTP transaction error while fetching from daemon@billhowell.ca@mail.lexi.net and delivering to SMTP host localhostW~Ilreading message daemon@billhowell.ca@mail-msa.lexi.net:1 of 2 (3658 octets)fetchmail: Query status=10 (SMTP)WlESI>ESI>ESI ESIVESIeESIrESIyESI ESIpESI rESI oESI mESI iESI sESIiESInESIgESI!ESRIpESI1https://gitlab.com/muttmua/mutt/-/wikis/MuttGuideESW1ESWESI+ESI-ESI-ESI-ESI-ESI-ESI+ESImail user agent (MUA)ESRESRESRESIMUAESI ESI-ESI ESI, the server that sends and queues mail - the mail transport agent (MTA), retrieval from remote mailboxes (MRA), local delivery and rewriting of messages - the mail delivery agent (MDA), and the remote submission of messages (MSA).ESRESUESR<?W(ESI?mESI@uESIAtESIBtESIC)ESR ESRESI ESI ESW ESI ESIMail Transfer Agent is anything between MUAs. MTAs generally do the routing and transferring of mail between hosts, ISPs, and so on, depending on how detailed one wants to be.ESRI ESWDESI ESRI ESI^Mail User Agent is a 'mail client program', the part you see and use to send and receive mail.ESROUESIOMRA - retrieval from remote mailboxes, local delivery and rewriting of messagesWOESWESI ESRI ESIMail Delivery Agent. An email arrives and does not need to go further. The MTA gives it to the Mail Delivery Agent, and the MDA puts it in an incoming mailbox. It might call other tools like procmail that then become part of its function.ESR#UESI#MSA - remote submission of messagesW#ESW#ESI ESRI ESIOn an ISP with lots of users that use MUAs on machines that don't have their own MTA, it is not enough to simply let all those users submit their messages to the MTA systems without any authentication. Otherwise spammers will exploit this and abuse the system. Accepting emails from users for sending elsewhere becomes a specialized task, and an MTA that does that is called the MSA.ESI ESRI ESIA Mail Retrieval Agent makes connections to a remote mailbox and fetches mail for local use. Fetchmail as a standalone program is a common example.ESW`I ESRI ESRI ESI-ESI ESIeMutt is an email client, and thus a MUA. Its POP&IMAP support means it has MRA functionality as well.ESRESRESRESRESR=DESI=(ESI>mESI?uESI@tESIAtESIB)ESI ESI ESI(ESI  ESI!aESI"sESI#nESI$dESR"#ESI$ ESI%procmailESI-)ESI ?ESI!?ESI"?ESWI ESIsendmail can be configured to simply pass on all mail and do nothing else fancy, see nullclient feature in cf/README or postfix-doc.ESR ESI(ESI sESI!eESI"nESI#dESI$mESI%aESI&iESI'lESI()ESRI ESRI ESI0,ESI1 ESI2mESI3aESI4iESI5lESI6dESI7rESI8oESI9pESIO ESIP ESIQ(ESIRfESISeESITtESIUcESIVhESIWmESIXaESIYiESIZlESI[)ESI[,ESI\ ESI]gESI^eESI_tESI`mESIaaESIbiESIclESId,ESIe ESIfrESIgeESIhtESIicESIjhESIkmESIlaESImiESInlESIo)ESI(,ESI) ESI*eESI+xESI,iESI-mESI.,ESI/ ESI0pESI1oESI2sESI3tESI4fESI5iESI6xESI7,ESI8 ESI9sESI:eESI;nESI<dESI=mESI>aESI?iESI@lESIA,ESIB ESICqESIDnESRDEESIDmESIEaESIFiESIGlESWI ESIbOn the internet, MTAs between themselves communicate via SMTP, the Simple Mail Transfer Protocol. ESR *E