Warning Codes
The table contains a list of current and upcoming warning types that the service can report on when processing an email address. These codes and notes will appear in the WarningCodes and WarningDescriptions fields.
Important Note!
New codes and descriptions will be added to the table as new features become available.
| Code | Warning | Description |
|---|---|---|
| 0 | UnrecognizedTLD | Indicates if the top-level-domain is not recognized by ICANN. |
| 1 | InvalidSyntax | Indicates if the email is syntactically invalid. |
| 2 | InvalidDomainSpecificSyntax | Indicates if email is syntactically invalid for the given domain. |
| 3 | InvalidDNS | Indicates if the domain is unregistered or it does not have at least one MX or A record configured to relay email. |
| 4 | NoMXRecords | Indicates that the registered DNS does not have an MX record. |
| 5 | Established | Indicates that the email address is known to be in bulk marketing lists. |
| 6 | Alias | Indicates if the email address is believed to be an alias address. |
| 7 | Bogus | Indicates if the email address is believed to be a bogus email. For example, asdf@asdf.com. |
| 8 | BogusSMSAddress | Indicates if the email address is believed to be a bogus SMS domain address. |
| 9 | Garbage | Indicates if the email address is believed to contain garbage-like keyboard strokes and/or garbage-like characters. |
| 10 | Vulgar [1] | Indicates if vulgar words or content are found in the email address. |
| 11 | MailBoxIsFull | Indicates if the mailbox is currently full and unable to receive any new messages. |
| 12 | MailboxIsBusy | Indicates if the mailbox is reported by the hosting mail server as being busy and unable to currently accept new messages. |
| 13 | DisposableEmail [2] | Indicates if the email address is believed to be disposable. Disposable email address are generally only valid for a short period of time before they are disposed and are then no longer valid. |
| 14 | SpamTrap | Indicates if the mailbox is believed to be a spam trap. |
| 15 | KnownSpammer | Indicates if the email address is known to have participated in spam-like activities. |
| 16 | BlacklistedDomain [3] | Indicates if the domain was found to be in one or more blacklists. |
| 17 | KnownComplainer | Indicates if the email address has been identified as a known complainer of receiving unsolicited mail. ** Coming Soon ** |
| 18 | KnownGreylister | Indicates if the mail server is known to commonly use greylisting techniques. This means that if your mail server is communicating with this domain for the first time or if you are sending bulk messages or messages in high frequency then you may be greylisted by them and experience temporary bounce backs. |
| 19 | OptInRequired | Indicates if the mail server requires opting-in to send and receive messages. |
| 20 | IsWhiteListOnly [3] | Indicates if the mail server only relays messages for users that are whitelisted. |
| 21 | ConnectionRefused | Indicates if the mail server refuses to accept an SMTP connection. |
| 22 | Email is Bad – Subsequent checks halted. | Indicates that the email address failed a critical check, such as SMTP verification. |
| 23 | Bot | Indicates that the email address failed a critical check, such as SMTP verification. |
Note Codes
The table contains a list of current and upcoming note types that the service can report on when processing an email address. These values will appear in the NotesCodes and NotesDescription fields.
Important Note!
New codes and descriptions will be added to the table as new features become available.
| Code | Note | Description |
|---|---|---|
| 0 | CCTLD | Indicates if the top-level-domain (tld) represents a specific country. For example “.us” implies United States. |
| 1 | Free | Indicates if the domain of the email is a public-register domain, where users can sign up for email accounts for free. |
| 2 | SMSDomain | Indicates if the domain is a known Mail-to-SMS Gateway. |
| 3 | Role | Indicates if the email address appears to be a role that is designed to be anonymously managed by one or more persons. |
| 4 | BusinessAddress | Indicates if the email address appears to be work related. |
| 5 | GreyListed [3] | Indicates if the mail server responded with a known greylist tactic. |
| 6 | MailServerTemporarilyUnavailable | Indicates that the mail server may be temporarily unavailable or too busy to respond. |
| 7 | ServerConnectTimeout | Indicates that a connection to the recipient mail server could not be established. |
| 8 | MailBoxTimeout | Indicates that the connection to the mail server timed out when trying to verify the email address. |
| 9 | TemporaryReject [4] | Indicates that the email address was temporarily rejected by the mail server. This is also known as a soft-bounce and the rejection is not permanent. There are many reasons for why a mail server may respond with a temporary reject. The mailbox or server may be busy, unavailable, or using a greylist. When a mail server does this it typically wants you to wait at least 15 minutes and then try again later. |
| 10 | SlowMailServer | Indicates that the host mail server is known to communicate slowly and that real-time verification of an email address may not be possible unless adequate time is provided. In some cases a timeout time of 90 seconds or more may be necessary to verify email addresses with these mail servers. |
| 11 | Varies Example: JP | ***Coming Soon: Countries: The ISO2 country code for the country where the mail server(s) is located. If mail servers are found in more than one country, then all country ISO2 codes will be represented in a pipe-delimited list. |
| 12 | Varies Example: OS|TY | ***Coming Soon: Region: The region in the country where the mail server(s) is located. The region is commonly returned as a two-character abbreviation. If mail servers are found in more than one region then the value will be a pipe-delimited list of the regions. |
| 13 | Varies Example: Osaka|Tokyo | ***Coming Soon: Localities: The name of the locality where the mail sever(s) is located in. If mail servers are found in more than one locality then the value will be a pipe-delimited list of all the localities. |
| 14 | Varies Example: 543-0062|102-0082 | ***Coming Soon: PostCodes: The post code of where the mail server(s) is located. If multiple post codes are found, then the value will be a pipe-delimited list. |
| 15 | SMTPCheckTimeout | Indicates that SMTP communication did not finish in the allotted time. It is recommend to increase the timeout time and try again. |
| 16 | TLS | Indicates that the recipient mail server supports Transport Layer Security (TLS) connections for encrypted email communication. |