SMTP Reply Codes

SMTP Reply Codes

See rfc2821 for the basic specification of SMTP; see also rfc1123 for important additional information.

See rfc1893 and rfc2034 for information about enhanced status codes.

SMTP Reply Codes List

Code Description
200 success response
211 System status, or system help reply
214 Help message
220 <domain> Service ready
221 <domain> Service closing transmission channel
250 Requested mail action okay, completed
251 User not local; will forward to <forward-path>
354 Start mail input; end with <CRLF>.<CRLF>
421 <domain> 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 unrecognized
501 Syntax error in parameters or arguments
502 Command not implemented
503 Bad sequence of commands
504 Command parameter not implemented
521 <domain> does not accept mail (see rfc1846)
530 Access denied ()
550 Requested action not taken: mailbox unavailable
551 User not local; please try <forward-path>
552 Requested mail action aborted: exceeded storage allocation
553 Requested action not taken: mailbox name not allowed
554 Transaction failed

SMTP Reply Codes By Command

Command Code Description
Connected
220 <domain> Service ready
421 <domain> Service not available, closing transmission channel
HELO
250 Requested mail action okay, completed
500 Syntax error, command unrecognized
501 Syntax error in parameters or arguments
504 Command parameter not implemented
521 <domain> does not accept mail [rfc1846]
421 <domain> Service not available, closing transmission channel
EHLO
250 Requested mail action okay, completed
550 Not implemented
500 Syntax error, command unrecognized
501 Syntax error in parameters or arguments
504 Command parameter not implemented
421 <domain> Service not available, closing transmission channel
MAIL FROM
250 Requested mail action okay, completed
552 Requested mail action aborted: exceeded storage allocation
451 Requested action aborted: local error in processing
452 Requested action not taken: insufficient system storage
500 Syntax error, command unrecognized
501 Syntax error in parameters or arguments
421 <domain> Service not available, closing transmission channel
RCPT
250 Requested mail action okay, completed
251 User not local; will forward to <forward-path>
550 Requested action not taken: mailbox unavailable
551 User not local; please try <forward-path>
552 Requested mail action aborted: exceeded storage allocation
553 Requested action not taken: mailbox name not allowed
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 unrecognized
501 Syntax error in parameters or arguments
503 Bad sequence of commands
521 <domain> does not accept mail [rfc1846]
421 <domain> Service not available, closing transmission channel
DATA
354 Start mail input; end with <CRLF>.<CRLF>
451 Requested action aborted: local error in processing
554 Transaction failed
500 Syntax error, command unrecognized
501 Syntax error in parameters or arguments
503 Bad sequence of commands
421 <domain> Service not available, closing transmission channel
SEND
250 Requested mail action okay, completed
552 Requested mail action aborted: exceeded storage allocation
451 Requested action aborted: local error in processing
452 Requested action not taken: insufficient system storage
500 Syntax error, command unrecognized
501 Syntax error in parameters or arguments
502 Command not implemented
421 <domain> Service not available, closing transmission channel
VRFY
250 Requested mail action okay, completed
251 User not local; will forward to <forward-path>
550 Requested action not taken: mailbox unavailable
551 User not local; please try <forward-path>
553 Requested action not taken: mailbox name not allowed
500 Syntax error, command unrecognized
501 Syntax error in parameters or arguments
502 Command not implemented
504 Command parameter not implemented
421 <domain> Service not available, closing transmission channel
Data Received
250 Requested mail action okay, completed
552 Requested mail action aborted: exceeded storage allocation
554 Transaction failed
451 Requested action aborted: local error in processing
452 Requested action not taken: insufficient system storage
RSET
200 (nonstandard success response, see rfc876)
250 Requested mail action okay, completed
500 Syntax error, command unrecognized
501 Syntax error in parameters or arguments
504 Command parameter not implemented
421 <domain> Service not available, closing transmission channel
SOML
250 Requested mail action okay, completed
552 Requested mail action aborted: exceeded storage allocation
451 Requested action aborted: local error in processing
452 Requested action not taken: insufficient system storage
500 Syntax error, command unrecognized
501 Syntax error in parameters or arguments
502 Command not implemented
421 <domain> Service not available, closing transmission channel
SAML
250 Requested mail action okay, completed
552 Requested mail action aborted: exceeded storage allocation
451 Requested action aborted: local error in processing
452 Requested action not taken: insufficient system storage
500 Syntax error, command unrecognized
501 Syntax error in parameters or arguments
502 Command not implemented
421 <domain> Service not available, closing transmission channel
EXPN
250 Requested mail action okay, completed
550 Requested action not taken: mailbox unavailable
500 Syntax error, command unrecognized
501 Syntax error in parameters or arguments
502 Command not implemented
504 Command parameter not implemented
421 <domain> Service not available, closing transmission channel
HELP
211 System status, or system help reply
214 Help message
500 Syntax error, command unrecognized
501 Syntax error in parameters or arguments
502 Command not implemented
504 Command parameter not implemented
421 <domain> Service not available, closing transmission channel
NOOP
200 (nonstandard success response, see rfc876)
250 Requested mail action okay, completed
500 Syntax error, command unrecognized
421 <domain> Service not available, closing transmission channel
QUIT
221 <domain> Service closing transmission channel
500 Syntax error, command unrecognized
TURN
250 Requested mail action okay, completed
502 Command not implemented
500 Syntax error, command unrecognized
503 Bad sequence of commands