Forum Discussion
Internal emails being treated as external emails
We have Exchange Online only - We have an application that sends out emails to users within the company however we have found an issue where all our distribution group recipients aren't getting the ...
The application sends the mail as this DL to other DL's and personal mailboxes (however the issue effects any application that sends emails to DL's)
The application is not on prem, we are fully cloud based but It is using an EXO connector.
However, it's since we added the EXO connector, these emails are being marked as "outside organization" but the IP's the mail is being sent from is authorized in the connector so I am at a bit of a loss on what's happened.
I assume you're using Option 3 from the below:
https://learn.microsoft.com/en-gb/Exchange/mail-flow-best-practices/how-to-set-up-a-multifunction-device-or-application-to-send-email-using-microsoft-365-or-office-365?redirectSourcePath=%252farticle%252fHow-to-set-up-a-multifunction-device-or-application-to-send-email-using-Office-365-69f58e99-c550-4274-ad18-c805d654b4c4
https://learn.microsoft.com/en-gb/Exchange/mail-flow-best-practices/how-to-set-up-a-multifunction-device-or-application-to-send-email-using-microsoft-365-or-office-365?redirectSourcePath=%252farticle%252fHow-to-set-up-a-multifunction-device-or-application-to-send-email-using-Office-365-69f58e99-c550-4274-ad18-c805d654b4c4
Similar scenario for us. We have an internal server set up as a relay. If we were using Option 2, would it be treated as internal or external emails?
As long as the connector is set up correctly as a "your org to office 365" connector it should be OK.
There isn't much to the config, I'm not sure how I could have this messed up. We do receive emails, but only if the distribution list is set to receive emails externally.
I identify via IP address. I also have the box checked to "retain internal Exchange email headers".
