SMTP Status Codes and Error Messages from Error 541 – 550
SMTP status code – 541 – Recipient Address Rejected – Access denied (typically by the recipient’s antispam program / appliance)
(also called SMTP Error 5.4.1)
SMTP Error 541 : This response is almost always sent
back by an anti-spam, intrusion prevention, or mail filtering
appliance / firewall at the recipient’s end.
Typically SMTP response 541 will be tagged along as a
sub-error of SMTP Error 550. For example : “SMTP
error from remote mail server – 550 5.4.1
firstname.lastname@example.org : Recipient address rejected
– Access Denied” or one from the Proventia anti-spam
appliance “#5.5.0 smtp;541 Internet Security Systems’
Proventia(TM) intrusion prevention appliance blocked
forwarding of message”.
The only way to solve SMTP Error 541 is to ask the
recipient to whitelist you.
SMTP status code – 550 – Requested actions not taken as the mailbox is unavailable.Usually it is at the recipient’s end, but it could also originate from inside your own “walls” through being caused, for example, by an appliance which scans your outgoing emails once they’ve left your server.
(also called SMTP Error 5.5.0)
550 is always a
problem external to
your own mail server.
SMTP Error 550 : This response can be caused by quite
a few situations.
550 is always a problem external to your own mail
server. Usually it is at the recipient’s end, but it could
also originate from inside your own “walls” through being
caused, for example, by a firewall appliance which scans
your outgoing emails once they’ve left your server.
SMTP Error 550 will be returned by many servers If the
recipient email address simply does not exist on the
remote side (you will often get “550 Invalid recipient” or
“550 User account is unavailable” or “<ip-address-ofremote-server>
does not like recipient – 550 Address
rejected” or “550 No such user here” or “550 Not our
Customer” or “550 Account not available” or “Remote
host said : 550 – Barack.Obama@ThisCompany.com, this
THISCOMPANY.COM Mailbox Does Not Exist – Giving
up”). In this case the sender of the email needs to contact
the recipient verbally to get the correct email address.
SMTP Error 550 will sometimes also be returned by the
recipient’s anti-spam firewall if, for example, the
anti-spam firewall does not like the sender (typically
because the sender needs to be whitelisted). A typical
example of an SMTP Error 550 return message by an
anti-spam firewall might be :
240.240.240.240 does not like recipient.
Remote host said: 550-Verification failed for
550-Previous (cached) callout verification failure
550 Sender verify failed
Giving up on 240.240.240.240.
SMTP Error 550 can also be returned by your own mail
and web filtering appliance where the message leaves
your mail server and is intercepted by your web and mail
filtering appliance, before it leaves your premises, and for
whatever configuration reasons it thinks your email is spam
or dangerous for the recipient (in other words it tries to
protect your company from accidentally sending viruses
and accidental spam emails – through a PC being infected
with a bot – to your customers). Here is a typical example
of such a response :
The attached file had the following undeliverable
Transcript of session follows:
Response: 550 Cyberoam Anti Spam Engine has identified
this email as a spam. Refid:str=0001.0A0B0206.4BA7422C.01F5,ss=1,vtr=str,vl=0,p
SMTP Error 550 will also be returned if the user’s
Above are list of SMTP Errors Codes and Status Codes along with Error and Warning messages from Error 541 – 550 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.