220 Service ready
This response is sent from the SMTP Server when a remote SMTP client or host attempts to connect to the server.
221 Service closing transmission channel
This response is sent from the server when the server is notifying the client that it is closing an active SMTP session.
250 Requested mail action okay, completed
This response indicates that a SMTP command was received by the server and successfully processed.
251 User not local; will forward to
This response is sent by the SMTP server to notify a remote SMTP server or client that the user requested in a RCPT command is not local to the server and that the server will relay the message to the appropriate host.
354 Start mail input; end with.
This response is sent by the SMTP server instructs a remote SMTP Server or client that the DATA command was accepted and that it can commence sending the actual message (first the message headers, then a [CRLF][CRLF] then the actual message body, concluded by [CRLF].[CRLF]).
421 Service not available, closing transmission channel
This response is sent by the SMTP Server to a remote SMTP Server or SMTP Client to indicate that the MailEnable SMTP Server is currently unavailable.
450 Requested mail action not taken: mailbox unavailable
This response is sent by the server to indicate that a message could not be addressed to a locally hosted recipient because the mailbox/mail address is not valid.
451 Requested action aborted: error in processing
This response is sent when the SMTP server incurred an error in processing an SMTP transaction.
452 Requested action not taken: insufficient system storage
This response indicates that the SMTP server has run out of disk space (or memory) and cannot accept an SMTP transaction.
500 Syntax error, command unrecognised
This response indicates that the server could not interpret a command that has been sent by the remote SMTP Server or client.
501 Syntax error in parameters or arguments
This response indicates that the server identified an attempt to issue an SMTP command but the parameters associated with the command contained a syntax error.
502 Command Not implemented
This response indicates that a feature or command requested of the server could not be accommodated because it is disabled or is not implemented by MailEnable s SMTP connector.
503 Bad sequence of commands
This response indicates that a remote SMTP Server or client is attempting to conduct a series of SMTP transactions out of sequence.
504 Command Not parameter
This response indicates that a command issued to MailEnable s SMTP connector contained another command that is unable to be processed within the same transaction.
550 Requested Not Action: mailbox unavailable or is not local.
This message indicates that the recipient specified in the RCPT command is not locally hosted on the server and relaying options prevent the message being forwarded to the recipient. To resolve this you should ensure that an address map has been associated with the desired mailbox. If you receive this message then you should use the MMC to ensure that this address has been assigned to a mailbox. This can be done in the MMC by viewing the properties of the Mailbox.
551 User not local; please try
This message indicates that the recipient specified in the RCPT command is not locally hosted on the server and relaying options prevent the message being forwarded to the recipient.
552 Requested mail action aborted: exceeded storage allocation
This response is returned by the server to either an RCPT or a DATA command if the user has exceeded their storage quota.
553 Requested Not Action: mailbox Not name
This response is issued by the server if the format of an SMTP address specified in an RCPT command is invalid or incorrectly formatted.
554 Transaction failed
This is a generic response returned by the server if an SMTP transaction failed. This response is typically returned if too many errors were received in processing.
