Exchange Server 2010 450 4.1.8 <>: Sender address rejected: Domain not found RRS feed

  • Question

  • I have exchange server 2010 and based server is windows server 2008 R2.

     450 4.1.8 <>: Sender address rejected: Domain not found ) error to some domains. I can successfully  nslookup to that domain .my smtpsend log shows 450 4.1.8 <>: Sender address rejected: Domain not found . please advice .. thank you.

    Wednesday, January 15, 2014 8:45 AM

All replies

  • Hi

    If you go to MXToolbox can you check that domain and see if any MX records exist?

    Wednesday, January 15, 2014 6:38 PM
  • yes , it dose exit .. I can find all their mx records .. and mine also both are not blacklisted.

    now mail Queue shows failed error 451 4.4.0 Primary target IP address responded with :"421 4.7.0 mx.theirservername Error:too many errors. "Attempted failover to alternate host but did not succeeded ...

    I would like to know is it their server fault or my DNS or mail server fault ? .. appreciate for any help , thank you .

    Thursday, January 16, 2014 1:54 AM
  • any update for this .. ??? I still cannot solve this problem .. the recipient side said my DNS has issue but I have checked all my A record mx record and I also can send to all other domain aside from theirs .. please guide me if there anymore steps to fix this
    Thursday, February 27, 2014 2:57 AM
  • Hi Amoeba,

    you need to point your primary and secondary DNS servers to Domain Hosting's dns. i am talking about DNS Forwarders. Thanks.

    Kindly mark this as answer if found helpful.

    Regards, Riaz Javed Butt | Consultant Microsoft Professional Services MCITP, MCITP (Exchange), MCSE: Messaging, MCITP Office 365 |

    Tuesday, May 20, 2014 3:39 AM