SMTP Connect fail intermediatly


  • Good Day,

    Exchange keeps on stopping receiving external emails, I noticed TELNETTing into the smtp server its intermediate sometimes it connects others it fails. Therefore causing problems receiving external emails. Any help would be highly appreciated.

    Thank you

    Tuesday, September 26, 2017 1:34 PM

All replies

  • Are all the services, particularly the transport services, running?

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

    Tuesday, September 26, 2017 3:31 PM
  • Hi,

    Check STMP service is working properly, Secondly check for Antivirus on Server might block connection.

    Also check for Firewall or some other app blocking this .

    Tuesday, September 26, 2017 5:44 PM
  • Hi,

    Thanks for contacting our forum.  Please help to verify the following questions:

    Does the Exchange server keeps fail receiving all the external domains or specific domain or randomly?

    Please check if any event recorded in the  App log.

    It’s also recommended to check the protocol log on your Exchange mailbox server via the following steps:

    1) Run following command to enable protocol log on all the send connectors on that Exchange server.

    Get-receiveconnector | Set-receiveconnector -protocollogginglevel verbose

    2) Try to reproduce the issue.

    3) Collect the latest SMTP log from following location on that server and post out the detailed error message if exist:

    C:\Program Files\Microsoft\Exchange Server\V15\TransportRoles\Logs\FrontEnd\ProtocolLog\SmtpReceive

    After that you need to run the command to disable it:

    Get-receiveconnector | Set-receiveconnector -protocollogginglevel none

    Make sure the driver of your server NIC is the latest version.

    Hope it helps.


    Jason Chao

    Please remember to mark the replies as answers if they help.
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    Wednesday, September 27, 2017 5:57 AM