Email provider · 4.x.x transient failure
Every SMTP 452 response on record from Yahoo Inc (yahoo.com, aol.com, verizon.net), with the verbatim text, the enhanced status code, a severity rating and a plain-English fix.
The action failed because the server is short on a resource, typically storage or the number of recipients it will take in one session. Sending fewer recipients per message, or simply retrying later, usually works.
smtp;452 temporary domain failure <example@example.com>
The receiver deferred this message and will retry it automatically. A failure that sticks around usually traces back to rate limits, reputation, or a policy on the receiving side.
Provider documentation
Postmaster & documentation
The action failed because the server is short on a resource, typically storage or the number of recipients it will take in one session. Sending fewer recipients per message, or simply retrying later, usually works. At Yahoo Inc, it is a temporary deferral that is retried automatically, and the specific reason is in the enhanced status code and message text of each response below.
Match your bounce text to one of the responses below and follow its guidance. Recipient-side wording means fix the address. Authentication or reputation wording (SPF, DKIM, DMARC, blocklist) means fix your sending setup, and check Yahoo Inc's postmaster documentation.
