SMTP 214 Help Message vs 535 Authentication Failed
SMTP 214 (Help Message) is a 2xx Positive Completion response, while 535 (Authentication Failed) 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, 535 means that the authentication credentials provided are invalid. The username, password, or authentication mechanism was rejected by the server.
Description
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.
When You See It
After sending the HELP command to the SMTP server. The response lists available commands or provides usage details for the command you specified.
How to Fix
No fix needed — this is a normal informational response. Use the provided help text to understand which commands the server supports.
Description
The authentication credentials provided are invalid. The username, password, or authentication mechanism was rejected by the server.
When You See It
After submitting incorrect credentials via the AUTH command. The username or password does not match any account on the server.
How to Fix
Double-check your username and password. If using an app password (e.g., Gmail, Outlook), ensure it is current and has not been revoked. Also verify the correct SASL mechanism (PLAIN, LOGIN, etc.).
Key Differences
214 is a 2xx Positive Completion response, while 535 is a 5xx Permanent Negative response.
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.
SMTP 535: The authentication credentials provided are invalid. The username, password, or authentication mechanism was rejected by the server.
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.
You encounter 535 when after submitting incorrect credentials via the AUTH command. The username or password does not match any account on the server.
When to Use Which
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 535 (Authentication Failed): Double-check your username and password. If using an app password (e.g., Gmail, Outlook), ensure it is current and has not been revoked. Also verify the correct SASL mechanism (PLAIN, LOGIN, etc.).