Emails bouncing back

Posted on 2012-08-14
Last Modified: 2012-08-16

I am getting bounced back emails from a certain email account. The message I get is...

The reason for the problem:
4.3.2 - Not accepting messages at this time 421-'4.7.0 [TS01] Messages
from temporarily deferred due to user complaints -

Thanks in advance

Question by:cbapartnership
    LVL 89

    Assisted Solution

    by:John Hurst
    You want to make sure you have Reverse DNS lookup working, but that does not appear to be the issue here.

    It appears that the target email system does not like you and the reason is normally excessive emailing or spam from the source.  

    Check that email relaying is turned off on your end and then contact Support for the target email system and ask them why they are bouncing your emails. Go from there.

    ... Thinkpads_User
    LVL 33

    Assisted Solution

    I'd agree with Thinkpads_User - your email server is sending excessive emails, to correct this check the email flow from your account to theirs using the following cmdlet

    Get-MessageTrackingLog -Resultsize Unlimited -Server "Name of Hub Server" | where {$_.Recipient -like "**"} | FT Sender,Recipients,Time*

    With the help of the result of the above cmdlet, you'll know how many emails are being generated for this domain.

    Alternately, contact the IT of this domain to gain more information about such rejection.

    LVL 21

    Expert Comment

    by:David Atkin
    Go to and verify that your domain is not on a blacklist.

    You may have been added to BT's IP block list.  If this is the case then you may have to contact BT and verify the nature of the 'user complaint'.

    Author Comment

    Thanks for the advice

    Exchange_Geek - Im not sure how to use the cmdlet that you mentioned. Can you elaborate on that for me please?

    Scorpeo  - According to mxtoolbox, we are on a spam list Spamhouse-ZEN
    LVL 21

    Accepted Solution

    Hi Scott,

    Okay - You need to remove your domain/IP from Spamhaus's black list.  See here:

    You have yo type in your IP/domain and then go through the form.

    To use Exchange_Geeks cmdlet you need to use the Exchange Shell.  Type in the command (replacing the hub server name with your exchange server name).  Can you confirm the Exchange version that you have?  I believe that command will work in Exchange 2007/2010.

    Doing a little more digging though, the IP address is a KC address.  It maybe worth forwarding the error message to and ask them to comment on it as well. - They are genuinely quite helpful (we deal with them alot).

    Author Closing Comment

    I have now got myself off the Spamhaus blacklist and informed Karoo about it. They also know about it too and they were making steps to sort it out. Spamhaus were blacklisting a range of IP's that Karoo were giving out.

    Thank you all very much for helping me in this matter. 10 out of 10
    LVL 21

    Expert Comment

    by:David Atkin
    Glad you got it sorted Scott.


    Write Comment

    Please enter a first name

    Please enter a last name

    We will never share this with anyone.

    Featured Post

    What Is Threat Intelligence?

    Threat intelligence is often discussed, but rarely understood. Starting with a precise definition, along with clear business goals, is essential.

    Granting full access permission allows users to access mailboxes present in their database. By giving full access permission one can open and read the content of any mailbox but cannot send emails from that mailbox.
    "Migrate" an SMTP relay receive connector to a new server using info from an old server.
    In this video we show how to create a Shared Mailbox in Exchange 2013. We show this process by using the Exchange Admin Center. Log into Exchange Admin Center.: First we need to log into the Exchange Admin Center. Navigate to the Recipients >> Sha…
    To add imagery to an HTML email signature, you have two options available to you. You can either add a logo/image by embedding it directly into the signature or hosting it externally and linking to it. The vast majority of email clients display l…

    737 members asked questions and received personalized solutions in the past 7 days.

    Join the community of 500,000 technology professionals and ask your questions.

    Join & Ask a Question

    Need Help in Real-Time?

    Connect with top rated Experts

    22 Experts available now in Live!

    Get 1:1 Help Now