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550 - 550-Requested action not taken: mailbox unavailable 550 invalid DNS MX or A/AAAA resource record ) RRS feed

  • Question

  • getting Error
    Message could not be sent to the following recipients: (550 - 550-Requested action not taken: mailbox unavailable
    550 invalid DNS MX or A/AAAA resource record
    )

    Any help would be apppreciated

    Saturday, June 18, 2016 6:56 PM

Answers

  • Hi,

    According to the error,"550 Requested action not taken: mailbox unavailable",it usually indicates that the e-mail address that was supposed to receive the message does not exist. Please check the spelling of the recipient's e-mail address and confirm whether the recipient is valid and his mailbox is available.

    About the error "550 invalid DNS MX or A/AAAA resource record",there may be a misconfiguration with the MX record.

    You can use Nslookup to check it. Please refer to the below link : https://technet.microsoft.com/en-us/library/aa998082(v=exchg.65).aspx

    Regards,                                                                          

    David


    • Marked as answer by Blinks Monday, June 20, 2016 5:49 PM
    Monday, June 20, 2016 7:52 AM
    Moderator

All replies

  • Fix the condition spelled out in the error message.  If you want more than that, you going to have to do more than just post an NDR.

    Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."
    Celebrating 20 years of providing Exchange peer support!

    Saturday, June 18, 2016 11:23 PM
    Moderator
  • Hi,

    According to the error,"550 Requested action not taken: mailbox unavailable",it usually indicates that the e-mail address that was supposed to receive the message does not exist. Please check the spelling of the recipient's e-mail address and confirm whether the recipient is valid and his mailbox is available.

    About the error "550 invalid DNS MX or A/AAAA resource record",there may be a misconfiguration with the MX record.

    You can use Nslookup to check it. Please refer to the below link : https://technet.microsoft.com/en-us/library/aa998082(v=exchg.65).aspx

    Regards,                                                                          

    David


    • Marked as answer by Blinks Monday, June 20, 2016 5:49 PM
    Monday, June 20, 2016 7:52 AM
    Moderator