Yahoo Inc

smtp;421 Service not available, closing transmission channel

Low severity

smtp;421 Max message per connection reached, closing transmission channel

smtp;421 4.7.0 [TSS04] Messages from 0.0.0.0 temporarily deferred due to unexpected volume or user complaints - 4.16.55.1; see https://postmaster.yahooinc.com/error-codes

High severity

smtp;450 User is receiving mail too quickly

Medium severity

smtp;451 example.yahoo.com Resources temporarily unavailable. Please try again later [#4.16.1].

Low severity

smtp;451 4.3.2 Internal server error

smtp;452 temporary domain failure <example@example.com>

smtp;501 Syntax error in parameters or arguments

smtp;550 relaying denied for <example@example.com>

smtp;552 1 Requested mail action aborted, mailbox not found

host xx.yahoodns.net [x.xx.xx.xx] SMTP error from remote mail server after MAIL FROM:<user@example.com> SIZE=2022: 553 5.7.1 [BL21] Connections will not be accepted from x.xx.xx.xx, because the ip is in Spamhaus's list; see http://postmaster.yahoo.com/550-bl23.html

Medium severity

host xx.yahoodns.net [x.xx.xx.xx] SMTP error from remote mail server after MAIL FROM:<user@example.com> SIZE=2022: 553 Mail from x.xx.xx.xx not allowed - 5.7.1 [BL23] Connections not accepted from IP addresses on Spamhaus XBL; see http://postmaster.yahoo.com/errors/550-bl23.html [550]

Medium severity

smtp;554 delivery error: dd This user doesn't have a example.com account (example@example.com) [-9] - example.yahoo.com

smtp;554 delivery error: dd Sorry, your message to example@example.com cannot be delivered. This mailbox is disabled (554.30). - example.yahoo.com

smtp;554 delivery error: dd Requested mail action aborted - example.yahoo.com

smtp;554 5.7.9 Message not accepted for policy reasons. See https://postmaster.yahooinc.com/error-codes

smtp;554 Message not allowed - [PH01] Email not accepted for policy reasons. Please visit https://postmaster.yahooinc.com/error-codes

High severity

smtp;554 Message not allowed - Headers are not RFC compliant[291]

smtp;554 Message not allowed - [299]

smtp;554 delivery error: dd example@example.com is no longer valid. [-20] - example.yahoo.com