Forum Discussion
Exchange Online - Mail User - without license and how to send email / SMTP access
The best way is to yuse method 3 on the following article. https://support.office.com/en-us/article/How-to-set-up-a-multifunction-device-or-application-to-send-email-using-Office-365-69f58e99-c550-4274-ad18-c805d654b4c4?ui=en-US&rs=en-US&ad=US&fromAR=1
For this kind of scenarios is what is best to implement and it's configured in several customers.
Yes, that one works best. We use it with cname on smtp.COMPANY.TLD. The connectors are somewhat restricted compared to Exchange on-premise.
cname is not ok, because of server certificates / ssl / tls..., so better use original server name.
Also, if you have dynamic public ip address, then this method is not possible.
It is better that Exchange team implement new functionality, something like Exchange Online - Application user, which will have username/password for SMTP submission, and will not require a license.
Yes, you are right again, cname has indeed drawback that the certificate does not match the name. I've chosen nonetheless for cname to make it easier to switch. TLS is not so strict currently in our nodes. But it is indeed not the right approach for optimal security.
It is possible to send for free, through Azure AD App and using Microsoft Graph API ...
