RFC 2034 Proposed Standard Transport

SMTP Service Extension for Returning Enhanced Error Codes

This memo defines an extension to the SMTP service [RFC-821, RFC-1869] whereby an SMTP server augments its responses with the enhanced mail system status codes defined in RFC 1893. [STANDARDS-TRACK]

Status
Proposed Standard. On the standards track and stable enough to implement against. Most of the email stack stays at this level permanently.
Published
October 1996
Authors
N. Freed
Read it
rfc-editor.org · DOI

What it is

The ENHANCEDSTATUSCODES extension, by which a server advertises that its replies carry RFC 3463 codes.

What it solves

Enhanced codes are only useful if a client knows to expect them.

What it means to operate

If a server advertises this and its replies do not carry enhanced codes, that is a bug worth reporting. If it does not advertise it, do not assume the numbers you find in the text are enhanced codes.

Bounce classifier turns an SMTP response into the action it calls for. Open bounce classifier

Normative requirements

Every sentence in this RFC carrying an RFC 2119 keyword, with the section it came from.

5 Status Codes and Negotiation

  • MUST NOTIt MUST NOT be taken as a license for future SMTP extensions to dramatically change the nature of SMTP client-server interaction without proper announcement from the server and a corresponding enabling command from the client.

Every current email RFC

Written and maintained by Rastu Singh, an infrastructure engineer working on high-volume email in Tallinn.