2.7.0Other or undefined security status (success)

The mail system reported a general security-related status that could not be described by a more specific code. The leading digit 2 denotes success, not message rejection.

The X.7.0 pattern denotes another or undefined security status: a security-related condition cannot be adequately expressed by any of the other detail codes, or an active security policy prevents a more detailed description. In the concrete code 2.7.0, the enhanced status class indicates success.

The leading digit 2 denotes success. Code 2.7.0 does not describe a temporary or permanent error and does not by itself confirm a bounce or rejection, even though its detail part concerns security.

Class

Success

Retry

Do not retry unchanged

Suppression

Check the full context

Do not retry based on code 2.7.0 alone because it is a success status. An automatic retry could create a duplicate; if the expected outcome is not visible, inspect the full event context first.

Do not add the recipient to a suppression list based solely on code 2.7.0. Make a suppression decision only after checking the context and other independent delivery or rejection events.

• The reporting system used the general X.7.0 pattern because the security-related condition could not be expressed by a more specific available code.
• An active security policy prevented the system from disclosing a more detailed description of the condition.

1. Inspect the raw SMTP response or DSN, confirm the exact code 2.7.0, and correlate the event with the intended message and send attempt.
2. If the code accompanies an SMTP reply, confirm that the basic reply is in the 2xx class and agrees with the enhanced 2.x.x class.
3. Review the complete response text, transaction stage, and later events; do not infer a specific authentication or policy cause from the general X.7.0 code.
4. If the system displays 2.7.0 as a bounce or rejection, trace the parser, normalization rules, and event mapping.

A verified provider example for 2.7.0 appears below, from Yahoo Mail. It shows real provider practice for this response and does not redefine the standard 2.7.0 meaning or cover every occurrence.

235 2.7.0 Authentication successful

Compare 4.7.0, 4.7.1, 4.7.12, and 4.7.15. These are related temporary class-4 security statuses, so they must not be handled in the same way as the successful 2.7.0 status.

• 4.7.0Other or undefined temporary security status
• 4.7.1Delivery not authorized, message temporarily refused
• 4.7.12Authentication mechanism transition required
• 4.7.15Priority level is too low

The code meaning and class assignment were verified against the IANA registry and RFC 2034, RFC 3463, and RFC 5248 as of July 17, 2026. Because no accepted provider example is available, no provider practice is attributed here. The retry, suppression, diagnostic, and owner-specific action guidance consists of separate, conservative operational recommendations; it is neither standards text nor a description of provider practice.

• iana-smtp-enhanced-status-codesT0 source

  Enumerated Status Codes / X.7.0

• rfc5248T0 source

  Section 2.1: registry fields and non-exclusive Associated Basic Status Code

• rfc2034T0 source

  Section 4: enhanced status class agrees with SMTP reply class

• rfc3463T0 source

  IANA registry reference for X.7.0

• ext-src-yahoo-aol-2-7-0-01T1 source

  Yahoo SMTP Protocol Exchange using OAUTHBEARER > authentication success (server line shown as 'S: 235 ...')

Last verified: 17 July 2026