From: God@heaven.af.mil From: The Boss <God@heaven.af.mil> From: firstname.lastname@example.org, email@example.com
According to 822, the From field ``contains the identity of the person(s) who wished this message to be sent.'' According to 822bis, the From field ``specifies the author(s) of the message, that is, the mailbox(es) of the person(s) or system(s) responsible for the writing of the message.''
822 requires that every message contain
From: Anonymous <firstname.lastname@example.org>People occasionally send messages without From fields. Outlook 98 (Corporate/Workgroup version, with Internet Mail Service, with the Outlook 98 Security Patch) omits From fields from local copies of outgoing messages.
Note that a From field cannot contain address groups:
From: sender-not-shown: ; (WRONG)Pine 3.95 reportedly crashes when it tries to read this field.
From: email@example.com Sender: firstname.lastname@example.orgAccording to 822, the Sender field ``contains the authenticated identity of the AGENT (person, system or process) that sends the message.'' According to 822bis, the Sender field ``specifies the mailbox of the agent responsible for the actual transmission of the message.''
822 specified Sender, defaulting to From, as the target of delivery failure notices and other bounce messages. This use of Sender was already obsolete at the time: bounce messages are sent to the Return-Path address. It is unclear why Sender is supposed to be useful.
I recommend against all automated use of Sender. In practice some programs create Sender as