Currently we have all of our Exchange accounts in 365.
I set myself to get the "postmaster" e-mails on undeliverable.
I am currently getting a lot of these?
Subject: Undeliverable: Your Flight Ticket Invoice 53518 - (our user)
Our we really sending these out? I am concerned and not sure how or why our spam is increasing.
I found this question on the website and it's what is going on with us. We have a spn record on our domain and they are coming frequent, so as of typing this, I"m unclear if there is anything or any other settings I can do to protect our domain?
Thank you for your help,