SMTP status codes

Hier die ursprüngliche Tabelle zur einfachen Übersicht:

SMTP Status Codes

Status 2xx „Success“

Code	Bedeutung
200	nonstandard success response (see rfc876)
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>

Status 3xx „Wait for“

Code	Bedeutung
354	Start mail input; end with <CRLF>.<CRLF>

Status 4xx „Temporary Error“

Code	Bedeutung
421	Service not available, closing transmission channel
422	The recipient has exceeded their mailbox limit
431	Not enough disk space on the delivery server; may be reported as out-of-memory error
432	the Administrator has frozen the queue
441	Intermittent network connection, the server has not yet responded
442	The server started to deliver the message but then the connection was broken
446	Too many hops. Most likely, the message is looping
447	Timeout occurred, check server connection
449	A DNS problem occurred; check your smart host setting on the SMTP connector
450	Requested mail action not taken: mailbox unavailable
451	Requested action aborted: local error in processing
452	Requested action not taken: insufficient system storage
465	Your server does not have the correct language code page installed

Status 5xx „Permanent Error“

Code	Bedeutung
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
510	Bad email address
511	Mailbox not found
513	Relaying denied or Address type incorrect
514	Two objects have the same address
515	Destination mailbox address invalid
516	Mailbox has been moved
517	Command violates RFC 821; most likely missing < > around email addresses
521	Server does not accept incoming mail
522	Recipient has exceeded their mailbox limit
523	Recipient cannot receive messages this big
524	Most likely, a distribution list or group is trying to send an email
530	Access denied
531	Mail system full; most likely Exchange database full
532	System not accepting network messages
533	Remote server has insufficient disk space to hold email
534	Message too big
535	Multiple Virtual Servers are using the same IP address and port; see MS KB321721 „Sharing SMTP“
540	There is no DNS server that can resolve this email address
541	No answer from host
542	Bad connection
543	Routing server failure, no route available
544	Cannot find the next hop, check the Routing Group Connector
546	Tricky looping problem, a contact has the same email address as an Active Directory user
547	Delivery time-out
548	Bad recipient policy
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, possibly more recipients than allowed
554	Transaction failed
555	Wrong protocol version
563	More than X attachments
571	Permission problem, most likely anonymous user is trying to send mail to distribution list
572	Distribution list cannot expand
573	External IP address of ISA server does not match SMTP publishing policy
574	Extra security features not supported, check delivery server settings
575	Cryptographic failure, try a plain message with encryption
576	Certificate problem, encryption level maybe too high
577	Message integrity problem

SMTP 550

Der Statuscode 550 (oder 5.5.0) scheint ein Spezialfall mit unterschiedlicher Bedeutung zu sein. Im besten Fall lässt sich über die mitgelieferte Text-Statusmeldung mehr herausfinden, zB. deutet „550 this address is not allowed“ auf einen unauthorisierten Benutzer hin (SMTP-Auth im Email Client vergessen?). Die textuelle Fehlermeldung ist in verschiedenen Email-Serverprodukten meist unterschiedlich formuliert. So bedeuten „550 queue expired“ unter Microsoft Exchange als auch „550 message expired“ unter MailEnable, dass die Nachricht nicht innerhalb der vorgegebenen Zeit zugestellt werden konnte.

Quellen und zusätzliche Informationen:

• RFC 1893: Enhanced Mail System Status Codes
• RFC 2034: SMTP Service Extension for Returning Enhanced Error Codes
• MailEnable KnowledgeBase: ME020032 – INF: SMTP Connector Inbound Response Codes