Dear Community, If you send a mail message to a large number of recipients ( e.g. 50 or more ), or you reply to all, you may experience a problem. K-9 Mail puts the long list of recipients in a single long line. If this line exceeds 999 characters, it is a SMTP protocol violation. An MTA like Postfix will choke on it. Other MUA's such as Thunderbird, Roundcube or Squirrelmail will insert line breaks between recipients names and addresses, and use continuation lines.
A bugfix could be made with the insertion of " CR LF space " after each comma found in the line, unless the comma appears in a display name between double-quotes. Frédéric On Tuesday, January 15, 2019 at 2:48:16 PM UTC+1, f-d-m wrote: > > Dear Community, > > The RFC standards mandate that no line longer than 999 chars may appear in > the raw message contents. > > When a mail with more than 20 or 30 recipients is being sent, the length > of the "To:" or "Cc:" may reach that limit and needs to be split in order > to fit. > > Other mail programs than K-9 tend to enumerate all the recipients one per > line, each line ending with a comma when continued, and each continuation > line starting with one or more spaces. > In opposition, K-9 places all the recipients in one single big line, then > splits it in fragments of 999 chars. Lines of more than 975 characters seem > to break downstream SMTP servers (Postfix ? OpenDKIM ? Postgrey ?) > > Has someone experienced in such cases pieces of the header appearing in > the e-mail body ? > > Has someone to complain that Gmail reject messages with the following > error message ? > > host gmail-smtp-in.l.google.com[108.177.127.27] > said: 550-5.7.1 [111.222.34.56 11] Our system has detected that this > message is 550-5.7.1 not RFC 5322 compliant: 550-5.7.1 'From' header is > missing. 550-5.7.1 To reduce the amount of spam sent to Gmail, this > message > has been 550-5.7.1 blocked. Please visit 550-5.7.1 > https://support.google.com/mail/?p=RfcMessageNonCompliant 550 5.7.1 and > review RFC 5322 specifications for more information. l26-v6si3298123eji.29 > - gsmtp (in reply to end of DATA command) > > Thank you all, > > Frédéric > Belgium > > -- You received this message because you are subscribed to the Google Groups "K-9 Mail" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
