Forum Discussion

Jeff Harlow's avatar
Jeff Harlow
Iron Contributor
Feb 23, 2018

Send Mail (SMTP) through Office 365 with MFA

We have a web server that needs to be able to send emails as users (FROM field); however, we have noticed that if the user account is protected with MFA, the message is rejected.  Has anyone been abl...
Authentication
exchange
office 365
security
Brian Reid's avatar
Brian Reid
MVP
Feb 28, 2018
Yes, which is why I said options 2 or 3, and both will work for you even if your Exchange hybrid role server is in Azure.

By the way, if they don't plan on maintaining an on-premises AD, what are the users going to login to? Unless you are going cloud accounts completely and turning off AD, you still need local domain controllers to the users for efficient login.
Jeff Harlow's avatar
Jeff Harlow
Iron Contributor
Feb 28, 2018

Per Microsoft's article that I originally included, Option 2 will not work for sending emails to external users (live.com, gmail.com, etc.)  

 

As far as what users will be logging into; Azure AD. 

 

  • Kazu1301's avatar
    Kazu1301
    Copper Contributor
    Aug 14, 2019

    Jeff Harlow , did you solve the issue? I am facing exactly the same problem here - the send-mailmessage was working at smtp.outlook365.com before enabling 2FA and after that I receive the same message you mentioned with no other changes. I also tried to use application specific password without success.  

    • Jeff Harlow's avatar
      Jeff Harlow
      Iron Contributor
      Aug 14, 2019

      We are using Option 3 now. Just configured the connector to allow the IPs for servers (in our case our external IP) to send mail and all works. No authentication required. Kazu1301 

      • Kazu1301's avatar
        Kazu1301
        Copper Contributor
        Aug 14, 2019

        Jeff Harlow thanks for your quick answer. I will consider the solution 3. The error message is very misleading. If the implementation of 2FA was not the only change made, I would misunderstand it and check other possibilities. Anyway, thanks a lot! 

  • Brian Reid's avatar
    Brian Reid
    MVP
    Mar 02, 2018
    Option 2 will work externally. You need to make sure your certificates for the connector contain your domain, or it will be treated as external email relaying. Option 3 is better. Option 2 is not there for allow mass marketing emails. But will work for a lower number of emails.

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