SMTP Status Codes and Error Messages from Error 220 to 251
SMTP status code – 220 – <Server Name> service is running
(SMTP Error 2.2.0)
SMTP Status 220 : This is normally the first message you
will get back from the server. It means the mail service is
running (ie. your mail server is running). It will normally
contain a welcome message and/or the title of the SMTP
software and, sometimes, the version number of the mail
server software. SMTP Reply 220 is effectively a “Hi
There, I have just this second finished starting up – I
am ready to go and at your command” informational
SMTP status code 221 – The domain service is closing the transmission channel
(SMTP Error 2.2.1)
SMTP Error 221 : The server is ending the mail session –
it is closing the conversation with the ISP as it has no more
mail to send in this sending session.
SMTP Status 221 is often misconstrued as an error
condition, when it is in fact nothing of the sort. The mail
server is simply telling you that it has processed everything
it was given in this particular session, and it is now going
back into waiting mode.
Because SMTP status 221 is often misinterpreted, with
some mail servers the Network Administrators have
changed the default text of SMTP Reply 221 to something
more meaningful and less alarming. For example, a typical
SMTP reply 221 might say “221 Goodbye” or
“221 Closing connection”, or the most irritating one we’ve
seen “221 Bye”, Arrrgghh – can you blame anyone for
thinking there might be a problem ? Of course not ! So
some Network Administrators are these days being quite
imaginative by changing the default text of SMTP reply 221
to more user friendly messages like : “221 Thank you for
your business” (I love that one!), or “221 All messages
processed successfully in this session, SMTP connection
SMTP status code 250 – Requested mail action OK completed
(SMTP Error 2.5.0)
SMTP Status 250 : The mail server has successfully
delivered the message! This is the best SMTP reply (250)
to receive – your message has been accepted and
transmitted OK ! J Yippee.
250 is effectively a status code rather than an error code –
there is no such thing as an SMTP error 250.
SMTP status code 251 – User not local will forward
(SMTP Error 2.5.1)
SMTP Status 251 : The email account is not local to the
ISP server but the ISP server will accept the email and will
forward it (the server will RELAY your message, this is the
most common action for ISP Mail servers – the recipient
will see your ISP in the mail header as one of the first hops
on the way to the recipient’s email system).
SMTP Error 251 is therefore more of an informational
message for technicians tracking how a message reached
Above are list of SMTP Errors Codes and Status Codes along with Error and Warning messages from Error 220 to 251 received while performing certain operation against mail server applications or related products.
What are SMTP Error Messages?
Simple Mail Transfer Protocol (SMTP) is an Internet standard for electronic mail (e-mail) transmission. SMTP protocol is used for sending e-mail messages between servers. Most e-mail systems that send mail over the Internet use SMTP to send messages from one server to another; the messages can then be retrieved with an e-mail client using either POP or IMAP.
In general, each SMTP error contains the following information:
• The SMTP Status Code or SMTP Error Codes or SMTP Reply Codes
• The message text. This text is usually returned with the Error code. Some messages employ word substitution, where the word substituted represents the system-replacement of a term more specific to the occurrence.
• An explanation of how the error may have occurred.
Hope this was helpful.
Information about SMTP Error Codes or Status Codes and Error Messages on Windows, Linux Operating Systems.