SMTP 250 OK vs 552 Exceeded Storage
SMTP 250 (OK) is a 2xx Positive Completion response, while 552 (Exceeded Storage) is a 5xx Permanent Negative response. 250 indicates that the requested mail action has been completed successfully. This is the most common positive response in SMTP, returned after HELO/EHLO, MAIL FROM, RCPT TO, and DATA completion. In contrast, 552 means that the requested mail action was aborted because the recipient's mailbox has exceeded its storage allocation. Unlike the temporary 452, this is a permanent rejection for this specific mailbox.
Descripción
The requested mail action has been completed successfully. This is the most common positive response in SMTP, returned after HELO/EHLO, MAIL FROM, RCPT TO, and DATA completion.
Cuándo lo verás
After nearly every successful SMTP command — greeting, specifying sender, adding recipients, or completing message delivery. This is the standard success confirmation.
Cómo solucionarlo
No fix needed — the command was accepted. If a command that should succeed returns a different code, check the command syntax and server policies.
Descripción
The requested mail action was aborted because the recipient's mailbox has exceeded its storage allocation. Unlike the temporary 452, this is a permanent rejection for this specific mailbox.
Cuándo lo verás
When the recipient's mailbox is completely full and cannot accept any more messages. The recipient needs to delete old emails or increase their quota.
Cómo solucionarlo
Notify the recipient through another channel that their mailbox is full. If you are the recipient, delete old messages or contact your mail administrator to increase the storage quota.
Diferencias clave
250 is a 2xx Positive Completion response, while 552 is a 5xx Permanent Negative response.
SMTP 250: The requested mail action has been completed successfully. This is the most common positive response in SMTP, returned after HELO/EHLO, MAIL FROM, RCPT TO, and DATA completion.
SMTP 552: The requested mail action was aborted because the recipient's mailbox has exceeded its storage allocation. Unlike the temporary 452, this is a permanent rejection for this specific mailbox.
You encounter 250 when after nearly every successful SMTP command — greeting, specifying sender, adding recipients, or completing message delivery. This is the standard success confirmation.
You encounter 552 when when the recipient's mailbox is completely full and cannot accept any more messages. The recipient needs to delete old emails or increase their quota.
Cuándo usar cada uno
For 250 (OK): No fix needed — the command was accepted. If a command that should succeed returns a different code, check the command syntax and server policies. For 552 (Exceeded Storage): Notify the recipient through another channel that their mailbox is full. If you are the recipient, delete old messages or contact your mail administrator to increase the storage quota.