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Kais_mbarki's avatar
Kais_mbarki
Brass Contributor
May 31, 2020

SMTP relay o365 (Send email from application or device to o365 in hybrid mode)

Hello,

can i send email to o365 with direct send method in hybrid configuration ?

 

the mail its send to local user in domaine o365 but not send to external user 

I have an exchange server 2013 hybrid with o365 and the MX is on o365 ( the traffic mail work correctly ) 

i put the  public @ip adresse in receive connector .. the mail its send to local user in domaine o365 but not send to external user from application when i want send notification to externe user 

we want to modify all notification in exchange to o365 , after that we remove the exchange 

 

 

i read this article and i configure the 3rd option 

https://docs.microsoft.com/en-us/exchange/mail-flow-best-practices/how-to-set-up-a-multifunction-device-or-application-to-send-email-using-office-3

thank you for help 

  • Although I do agree with you Peter on leaving the last Exchange server in place, the option stated by Kais_mbarki should work.
    Requirements are creating a connector in EXO from his WAN IP (or option e-mail server of your org in the EXO ECP) to Office 365 and adding a whitelist entry for the IP in EXO as well.
    If you then specify your Office 365 "MX record" so your-domain-com.onmicrosoft.com in the app as the mail server with port set to 25 and SSL to ON it should work.
    I have several clients who are using Office 365 as a relay server this way.
    By the way, I wouldn't suggest using the authentication method anymore because basic auth support will be discontinued in the future.
  • Kais_mbarki 

     

    Hi, in an Exchange Hybrid environment, the preferred method to SMTP relay is through the Exchange Hybrid server itself. 

     

    I note that you are planning to remove your Exchange server?  If you do this, and continue synchronising your AD to Azure AD, then you will be putting yourself in a position where you are not supported by Microsoft.

     

    So I would recommend keeping at least one Exchange Server to act as Management Server and SMTP relay.

    • BemmelenPatrick's avatar
      BemmelenPatrick
      Iron Contributor
      Although I do agree with you Peter on leaving the last Exchange server in place, the option stated by Kais_mbarki should work.
      Requirements are creating a connector in EXO from his WAN IP (or option e-mail server of your org in the EXO ECP) to Office 365 and adding a whitelist entry for the IP in EXO as well.
      If you then specify your Office 365 "MX record" so your-domain-com.onmicrosoft.com in the app as the mail server with port set to 25 and SSL to ON it should work.
      I have several clients who are using Office 365 as a relay server this way.
      By the way, I wouldn't suggest using the authentication method anymore because basic auth support will be discontinued in the future.
      • Kais_mbarki's avatar
        Kais_mbarki
        Brass Contributor
        Thank you,
        it worked following the change from organization type connectors to mail server type

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