Stéphane Bortzmeyer @stephane CC BY-SA 19/09/2014 “#Email History through #RFCs”▻https://wordtothewise.com/2014/09/email-history-rfcs Stéphane Bortzmeyer @stephane CC BY-SA
liotier @liotier CC BY-SA 13/05/2014 What 4xx/5xx rejection codes could mean at the various stages of an #SMTP transaction:▻https://wordtothewise.com/2014/05/smtp-level-rejections liotier @liotier CC BY-SA