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SMTP error codes


200 (nonstandard success response, see rfc876)
211 System status, or system help reply
214 Help message
220 Service ready
221 Service closing transmission channel
250 Requested mail action okay, completed
251 User not local; will forward to
252 Cannot VRFY user, but will accept message and attempt delivery
354 Start mail input; end with.
421 Service not available, closing transmission channel
450 Requested mail action not taken: mailbox unavailable
451 Requested action aborted: local error in processing
452 Requested action not taken: insufficient system storage
500 Syntax error, command unrecognised
501 Syntax error in parameters or arguments
502 Command not implemented
503 Bad sequence of commands
504 Command parameter not implemented
521 does not accept mail (see rfc1846)
530 Access denied (???a Sendmailism)
550 Requested action not taken: mailbox unavailable
551 User not local; please try
552 Requested mail action aborted: exceeded storage allocation
553 Requested action not taken: mailbox name not allowed
554 Transaction failed