I have a number of systems on my network that send email via smtp port 25: scanners, fax machines, apps, etc.
They are all configured to send to my exchange 2007 hub transport server.
I setup a receive connector with the ip addresses of every device that sends to it.
I am in the process of migrating to Office 365 \ Exchange Online.
I setup an exchange 2013 hybrid server.
Everything is working fine, except, some emails from some application servers or systems are ending up in my users' junk mail folder.
My users' junk mail option is set to High. We don't want to change this and we do not want to use safe a senders list. Too much work to maintain for all users.
The exchange 2013 hybrid server's Default FrontEnd receive connector accepts internal port 25 smtp connections.
If I reconfigure my email sending systems and apps to send to the exchange 2013 hybrid server, will this prevent these emails from being junked?