SMTP code 452
What the knowledge base's own tables say about this code, and which articles say it — a description of the reply, never a placement prediction.
The knowledge base documents this code in more than one row. What tells those rows apart is the rejection text in your own log, not the code: read each line below against what your rejection says.
- Meaning
- Insufficient system storage, or too many recipients; retry
This line comes from a knowledge base article on Comcast, not on the standard.
- Meaning
- More than 1,000 messages in the session
- Message
- Too many emails sent on this session
From Comcast / Xfinity — Postmaster: Error Codes, Rate Limits, Unblocking · Generic SMTP errors
This line comes from a knowledge base article on Comcast, not on the standard.
- Meaning
- More than 100 recipients for the message
- Message
- Too many recipients for message
From Comcast / Xfinity — Postmaster: Error Codes, Rate Limits, Unblocking · Generic SMTP errors
- Meaning
- Too many emails or recipients, or the server's storage limit was exceeded
From DNS Blocklists and the Spamhaus Zones · Bounce handling