The autodiscover process checks a few records , one of these is the root domain A record, and once you have an SSL certificate on your Web Server under cPanel, it intercepts the Autodiscover request cPanel believes it is hosting the email, and directs that to itself to its email servertrying to be helpful ( Instead of your Exchange server or 365 ) .

The email users are not setup on your cpanek, so no matter what you try, you will not be able to setup the user’s Outlook profile. This is the error I was getting in Outlook 2016. The error will be different for other versions of Outlook or if you are setting up the profile from Control Panel, but essentially it will not let you complete the profile setup.

The fix is quite simple, you just need to change the setting in cPanel or WHM (also owned by cPanel) from the default setting of “Local Mail Exchanger” to “Remote Mail Exchanger” and that’s it.