Not able to send mails to external world. RRS feed

  • Question

  • Hi All,

    I am in mid of the way where i have to migrate exchange 2010 to 2016 , iam in the testing phase , where mailflow is internally fine but when i am sending mails to external world its dropping . I have created same connectors are available in 2010 .

    Today had a look at the email flow for both mailboxes hosted on both Exchange 2010 and Exchange 2016
    Outbound Emails sent from Exchange 2010 mailbox looks good
    Outbound Emails sent from Exchange 2016 mailbox failed as below.

    RunspaceId                       : f8269265-572d-4779-99cd-75865b067524
    DeliveryType                     : DnsConnectorDelivery
    NextHopDomain                    : xxx.com
    TlsDomain                        : 
    NextHopConnector                 : f730d878-ab91-4330-83d5-a9c70c364cd8
    Status                           : Retry
    MessageCount                     : 11
    LastError                        : [{LED=451 4.4.397 Error communicating with target host. -> 421 4.2.1 Unable to  connect -> SocketTimedout: Socket error 

    please advice .



    Wednesday, July 31, 2019 6:26 AM

All replies

  • Hello,

    are you able to telnet your gateway?

    is your exchange 2016 IP or hostname is white-listed on your smart host ?


    Wednesday, July 31, 2019 12:08 PM