SMTP 235 Authentication Successful vs 530 Authentication Required
SMTP 235 (Authentication Successful) is a 2xx Positive Completion response, while 530 (Authentication Required) is a 5xx Permanent Negative response. 235 indicates that the client has been successfully authenticated using the AUTH command. The server will now accept mail commands from this authenticated session. In contrast, 530 means that the server requires authentication before accepting mail commands. You must issue the AUTH command with valid credentials before attempting to send mail.
Descripción
The client has been successfully authenticated using the AUTH command. The server will now accept mail commands from this authenticated session.
Cuándo lo verás
After submitting valid credentials via the AUTH command (LOGIN, PLAIN, or other SASL mechanism). The server has verified your identity and you can now send mail.
Cómo solucionarlo
No fix needed — authentication succeeded. If you expected this but received a different code, double-check your username, password, and the authentication mechanism.
Descripción
The server requires authentication before accepting mail commands. You must issue the AUTH command with valid credentials before attempting to send mail.
Cuándo lo verás
When trying to send mail through a server that requires authentication (typical for submission on port 587) without first logging in with the AUTH command.
Cómo solucionarlo
Authenticate using the AUTH command with your username and password before sending MAIL FROM. Ensure your email client is configured with the correct SMTP credentials and authentication method.
Diferencias clave
235 is a 2xx Positive Completion response, while 530 is a 5xx Permanent Negative response.
SMTP 235: The client has been successfully authenticated using the AUTH command. The server will now accept mail commands from this authenticated session.
SMTP 530: The server requires authentication before accepting mail commands. You must issue the AUTH command with valid credentials before attempting to send mail.
You encounter 235 when after submitting valid credentials via the AUTH command (LOGIN, PLAIN, or other SASL mechanism). The server has verified your identity and you can now send mail.
You encounter 530 when when trying to send mail through a server that requires authentication (typical for submission on port 587) without first logging in with the AUTH command.
Cuándo usar cada uno
For 235 (Authentication Successful): No fix needed — authentication succeeded. If you expected this but received a different code, double-check your username, password, and the authentication mechanism. For 530 (Authentication Required): Authenticate using the AUTH command with your username and password before sending MAIL FROM. Ensure your email client is configured with the correct SMTP credentials and authentication method.