SMTP 250 OK vs 500 Syntax Error
SMTP 250 (OK) is a 2xx Positive Completion response, while 500 (Syntax Error) 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, 500 means that the server could not recognize the command due to a syntax error. The command line was malformed or the command is not recognized by this server.
Açıklama
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.
Gördüğünüzde
After nearly every successful SMTP command — greeting, specifying sender, adding recipients, or completing message delivery. This is the standard success confirmation.
Nasıl Düzeltilir
No fix needed — the command was accepted. If a command that should succeed returns a different code, check the command syntax and server policies.
Açıklama
The server could not recognize the command due to a syntax error. The command line was malformed or the command is not recognized by this server.
Gördüğünüzde
When you send a command the server does not understand — often due to a typo, unsupported command, or an excessively long line.
Nasıl Düzeltilir
Check the command spelling and syntax against the SMTP specification. Ensure the command line does not exceed 512 characters and uses proper CRLF line endings.
Temel Farklar
250 is a 2xx Positive Completion response, while 500 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 500: The server could not recognize the command due to a syntax error. The command line was malformed or the command is not recognized by this server.
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 500 when when you send a command the server does not understand — often due to a typo, unsupported command, or an excessively long line.
Hangisini Ne Zaman Kullanmalı
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 500 (Syntax Error): Check the command spelling and syntax against the SMTP specification. Ensure the command line does not exceed 512 characters and uses proper CRLF line endings.