I am setting up automated email functionality for an application. We are on 365.
I need to setup a mailbox so that the server / software can authentication with 365 when sending the email. However, I don't want it to save anything. I don't want the sent messages to accumulate in the shared mailbox's. Sent Items or anywhere else. This is because there could be some confidential information, and I think it is best to not save it anywhere unnecessarily.
How do I do that? How do I setup a mailbox that can authenticate and send mail, but not actually store the mail that it sends?
I looked in the transport rules, but didn't see any options that looked like what I wanted. I also looked at the Retention policy. It looks like there is a 1 day policy for sent items. I could use that, but I was hoping to not store at all.