SMTP 250 OK vs 452 Insufficient Storage
SMTP 250 (OK) is a 2xx Positive Completion response, while 452 (Insufficient Storage) is a 4xx Transient 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, 452 means that the requested action was not taken because the server has insufficient system storage. The server cannot accept more mail until storage is freed.
Descrição
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.
Quando você o vê
After nearly every successful SMTP command — greeting, specifying sender, adding recipients, or completing message delivery. This is the standard success confirmation.
Como corrigir
No fix needed — the command was accepted. If a command that should succeed returns a different code, check the command syntax and server policies.
Descrição
The requested action was not taken because the server has insufficient system storage. The server cannot accept more mail until storage is freed.
Quando você o vê
When the mail server's disk is full or the recipient's mailbox has exceeded its storage quota. The server cannot store additional messages.
Como corrigir
If you are the sender, retry later after the recipient frees up space. If you manage the server, clear disk space, increase quotas, or archive old messages.
Diferenças principais
250 is a 2xx Positive Completion response, while 452 is a 4xx Transient 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 452: The requested action was not taken because the server has insufficient system storage. The server cannot accept more mail until storage is freed.
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 452 when when the mail server's disk is full or the recipient's mailbox has exceeded its storage quota. The server cannot store additional messages.
Quando usar qual
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 452 (Insufficient Storage): If you are the sender, retry later after the recipient frees up space. If you manage the server, clear disk space, increase quotas, or archive old messages.