SMTP

SMTP 214 Help Message vs 503 Bad Sequence

SMTP 214 (Help Message) is a 2xx Positive Completion response, while 503 (Bad Sequence) is a 5xx Permanent Negative response. 214 indicates that a help message response containing information about the server's supported commands or a specific command's usage. This is a human-readable reply to the HELP command. In contrast, 503 means that the commands were sent in the wrong order. SMTP requires a specific command sequence (EHLO, MAIL FROM, RCPT TO, DATA) and this error indicates a step was skipped or repeated.

Mô tả

A help message response containing information about the server's supported commands or a specific command's usage. This is a human-readable reply to the HELP command.

Khi bạn thấy mã này

After sending the HELP command to the SMTP server. The response lists available commands or provides usage details for the command you specified.

Cách khắc phục

No fix needed — this is a normal informational response. Use the provided help text to understand which commands the server supports.

Mô tả

The commands were sent in the wrong order. SMTP requires a specific command sequence (EHLO, MAIL FROM, RCPT TO, DATA) and this error indicates a step was skipped or repeated.

Khi bạn thấy mã này

When sending DATA before RCPT TO, or MAIL FROM before EHLO. The server enforces the correct SMTP command sequence and you have sent a command out of order.

Cách khắc phục

Follow the proper SMTP command sequence: EHLO/HELO first, then MAIL FROM, then RCPT TO (one or more), then DATA. Reset with RSET if you need to start over.

Sự khác biệt chính

1.

214 is a 2xx Positive Completion response, while 503 is a 5xx Permanent Negative response.

2.

SMTP 214: A help message response containing information about the server's supported commands or a specific command's usage. This is a human-readable reply to the HELP command.

3.

SMTP 503: The commands were sent in the wrong order. SMTP requires a specific command sequence (EHLO, MAIL FROM, RCPT TO, DATA) and this error indicates a step was skipped or repeated.

4.

You encounter 214 when after sending the HELP command to the SMTP server. The response lists available commands or provides usage details for the command you specified.

5.

You encounter 503 when when sending DATA before RCPT TO, or MAIL FROM before EHLO. The server enforces the correct SMTP command sequence and you have sent a command out of order.

Khi nào dùng cái nào

For 214 (Help Message): No fix needed — this is a normal informational response. Use the provided help text to understand which commands the server supports. For 503 (Bad Sequence): Follow the proper SMTP command sequence: EHLO/HELO first, then MAIL FROM, then RCPT TO (one or more), then DATA. Reset with RSET if you need to start over.

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