Question
If at any stage in an SMTP transaction there is an error, it will have a unique code assigned to it so the user can hopefully determine why it has happened.
However the response codes are not always errors,
SMTP will also output a success code.
The first digit of the response denotes whether it is good, incomplete or simply bad.
2 – Success reported
4 – Temporary failure
5 – Permanent failure
Answer
Here are a list of known codes:
Response code | Description |
---|---|
211 | System status or system help reply |
214 | Help message |
220 |
|
221 |
|
250 | Requested mail action okay, completed |
283 | The Gordano server is configured so that messages aren’t being saved. The FROM and TO address are taken from the e-mail message headers |
354 |
Start mail input; end with |
421 |
|
450 | Requested action not taken; mailbox unavilable or busy |
451 | Requested action aborted, local error in processing |
452 | Requested action not taken, insufficient system storage |
500 | Syntax error, command unrecognized. Also command line too long |
501 | Syntax error in paramaters or arguements |
502 | Command not implemented |
503 | Bad sequence of commands |
504 | Command parameters not implemented |
550 | Action not taken. Mailbox unavailable. Not found, not accessible |
551 |
User not local, please try |
552 | Exceeded storage allocation |
553 | Mailbox name not allowed. Mailbox syntax may be incorrect |
554 | Transaction failed |
See Also:
- What is the SMTP MAIL clause?
- What is the SMTP VRFY clause?
- What is the SMTP RCPT clause?
- What is the SMTP DATA clause?
- What is the SMTP HELO/EHLO clause?
- What is SMTP Response Code Theory?
Keywords:SMTP response code theory error