Email provider
Yahoo Inc SMTP Error Codes and Bounce Messages
Yahoo handles mail for the yahoo.com, aol.com and verizon.net families. It publishes clear sender requirements and offers a postmaster site plus a complaint feedback loop for investigating misclassified mail.
- Codes on record
- 9
- Responses
- 20
- Domains
- yahoo.com, aol.com, verizon.net
Postmaster & documentation
SMTP 4213 responses
smtp;421 Service not available, closing transmission channel
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
A temporary problem. The sending server keeps retrying for a while, and delivery often recovers on its own once the underlying issue clears. See SMTP 421 across every provider
SMTP 4501 response
A temporary problem. The sending server keeps retrying for a while, and delivery often recovers on its own once the underlying issue clears. See SMTP 450 across every provider
SMTP 4512 responses
A temporary problem. The sending server keeps retrying for a while, and delivery often recovers on its own once the underlying issue clears. See SMTP 451 across every provider
SMTP 4521 response
A temporary problem. The sending server keeps retrying for a while, and delivery often recovers on its own once the underlying issue clears. See SMTP 452 across every provider
SMTP 5011 response
A hard failure. The receiving server has refused the message for good and will not accept an unchanged retry without a change on the sending side. See SMTP 501 across every provider
SMTP 5501 response
A hard failure. The receiving server has refused the message for good and will not accept an unchanged retry without a change on the sending side. See SMTP 550 across every provider
SMTP 5521 response
A hard failure. The receiving server has refused the message for good and will not accept an unchanged retry without a change on the sending side. See SMTP 552 across every provider
SMTP 5532 responses
host xx.yahoodns.net [x.xx.xx.xx] SMTP error from remote mail server after MAIL FROM:<[email protected]> 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
host xx.yahoodns.net [x.xx.xx.xx] SMTP error from remote mail server after MAIL FROM:<[email protected]> 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]
A hard failure. The receiving server has refused the message for good and will not accept an unchanged retry without a change on the sending side. See SMTP 553 across every provider
SMTP 5548 responses
smtp;554 delivery error: dd This user doesn't have a example.com account ([email protected]) [-9] - example.yahoo.com
smtp;554 delivery error: dd Sorry, your message to [email protected] 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
A hard failure. The receiving server has refused the message for good and will not accept an unchanged retry without a change on the sending side. See SMTP 554 across every provider
Yahoo Inc bounce questions
›Why is Yahoo Inc bouncing my email?
Yahoo handles mail for the yahoo.com, aol.com and verizon.net families. It publishes clear sender requirements and offers a postmaster site plus a complaint feedback loop for investigating misclassified mail. Match the exact wording of your bounce to one of the 20 responses on this page to find the specific reason and fix.
›How do I improve deliverability to Yahoo Inc?
Authenticate with SPF, DKIM and DMARC, keep your sending IP and domain reputation clean, mail only engaged recipients, and honour unsubscribes. Yahoo Inc also publishes postmaster guidance, linked on this page.
