SMTP Status Codes and Error Messages from Error 447 to 450


SMTP status code – 447 – Your outgoing message timed out.
(also called SMTP Error 4.4.7)
SMTP Error 447 : Your outgoing message timed out
because of problems with the receiving server who
objected to your message. Typically there is a problem
with the message header (such as too many recipients, in
most cases, or a protocol timeout between the two

SMTP status code – 449 – Routing error
(also called SMTP Error 4.4.9)
SMTP Error 449 : This is a Microsoft Exchange Server
specific error code. As per Microsoft’s documentation this
error code is returned when either of the following
conditions occurs : an SMTP connector is configured to
use DNS without a smart host and also uses a non-SMTP
address space (e.g. X.400), or A message was sent to a
recipient who was identified as a member of a routing
group that was deleted.
Microsoft recommends using the WinRoute tool to
troubleshoot this error (Microsoft Knowledgebase article

SMTP status code – 450 – Requested action not taken – The mailbox was unavailable at the remote end. A secondary SMTP error code may follow “450” to refine the
reason for the failure to transmit the message, e.g. “SMTP Error 450
(also called SMTP Error 4.5.0)
SMTP Error 450 : The server could not access the
mailbox to deliver the message. This could be caused by
a process on the remote server tidying up the mailbox, or
the remote mailbox could be corrupt, or the remote mailbox
may be stored on another server which is currently offline,
or the network connection went down while sending, or the
remote mail server does not want to accept mail from your
server for some reason (IP address, blacklisting, etc..).
In general SMTP Error 450 is a transient error at the
remote end (the destination), or at one of the routers
or servers en route to the remote end, and should
induce your mail server to retry after it’s preset retry
interval. Example of an SMTP Error 450 reply message :
“450 Please try again later”, or a classic Novell GroupWise
450 status message : “The message that you sent has
been delayed. The reason given for the delay: 450 Host
down (”.
SMTP Error 450 is often followed by a second SMTP error
code to refine the reason for the email not reaching its
destination. For example : “SMTP Error 450 5.2.3 Msg
Size greater than allowed by Remote Host”. When that is
the case and If the error message is not as clearly worded
as in this example, then simply search this document for
the secondary error code. In this case searching this
document for SMTP Error 523 or SMTP Error 5.2.3 would
yield an explanation identical to the wording above.

Above are list of SMTP Errors Codes and Status Codes along with Error and Warning messages from Error 447 to 450 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.

SQLServerF1 Team
Information about SMTP Error Codes or Status Codes and Error Messages on Windows, Linux Operating Systems.


Leave a Reply

Your email address will not be published. Required fields are marked *