Most common SMTP errors with a short description. If you are a client of Tomahawk Technologies Inc. please cotnact us to resolve any issues.
| Code | En. Code | Message | Description |
| 500 | 5.5.1 | Command unrecognized | The SMTP command currently used was unrecognized or is not supported by the server. |
| 501 | 5.5.2 | Domain name required | Sender has no domain specified (usually in MAIL FROM) |
| 501 | 5.5.2 | Unbalanced | SMTP session syntax invalid. (usually unbalanced brackets) |
| 501 | 5.5.4 | Syntax error in parameters scanning | Common syntax error. You probably mistyped last command or last string is invalid. |
| 501 | 5.5.1 | HELO/EHLO requires domain address | Usually when there was blank or invalid string sequence after HELO/EHLO command. |
| 501 | 5.0.0 | Authentication cancelled | The process of authentication was cancelled for any reason. |
| 501 | 5.7.0 | Authentication failed | The username/password combination provided during authentication was invalid. |
| 501 | 5.7.1 | You are not allowed to send. | |
| 502 | 5.5.1 | Sorry, we do not support this operation | This operation is not allowed. |
| 503 | 5.5.1 | Incorrect command sequence | A supported command was used on invalid place. For example command RCPT TO used before MAIL FROM or DATA command used when RCPT TO command was not accepted. |
| 503 | 5.5.1 | Authentication already done | Error occurs by re-authentication. |
| 503 | 5.5.1 | HELO/EHLO command required | Greeting error. HELO/EHLO command is required. |
| 503 | 5.5.1 | HELO/EHLO already specified | Greeting used again. |
| 504 | 5.7.6 | Unrecognized authentication type | Invalid authentication type. Incorrect or none type of AUTH specified. |
| 530 | 5.7.1 | Authentication required [AUTH] | Authentication with command AUTH is required. |
| 550 | 5.7.1 | We do not relay | Server is not open for relay. |
| 550 | 5.7.1 | We do not relay, account limits apply | |
| 550 | 5.7.1 | You have rights to send mail to local domains only | The user who gets this error is allowed to send mail only to local domains. |
| 550 | 5.7.1 | Access not allowed | 1)SMTP Server blocked access by a black list filter. or 2) reject if originator's domain is local and not authorized option turned on |
| 550 | 5.7.1 | Permission denied | Occurs after a delay from original connection time. |
| 550 | 5.1.1 | Unknown user local | |
| 550 | 5.1.1 | Unknown user; rejecting | Unknown user account. The recipient is not local, thus reject the message. |
| 551 | 5.1.1 | No such user found | User account is not local. |
| 551 | 5.1.1 | No such mailing list found | Mailing list is not local. |
| 552 | 5.5.3 | Too many recipients | The number of recipients exceeds the maximum of allowed recipients. |
| 554 | 5.3.4 | Message size exceeds fixed maximum message size | Too many data was sent by the user. User account has an amount limitation. |
| 554 | 5.7.1 | Message cannot be accepted, virus found | Virus was found in the message body or in the message attachment. |
| 554 | 5.7.1 | Message cannot be accepted, content filter rejection | Content filter applied and the message was rejected. |
| 554 | 5.7.1 | Message cannot be accepted, spam filter rejection | Message is probably spam. |
| 554 | 5.7.1 | Message cannot be accepted, spam rejection | Message is probably spam. |
| Message deleted by filter | |||
| Message challenged by filter | |||
| 554 | 5.2.2 | Maximum size exceeded. | |
| 554 | 5.3.1 | Maximum message size exceeded. | |
| 554 | 5.7.1 | Message cannot be accepted, filter rejection | The message was rejected. |
