Not sure if this is possible or not, I'm using DNN 5.4 on a server outside of my network for a website.  Under Host settings > SMTP settings, I'm trying to point the mail server to my external mail server, but cannot get it to work.

I've tried all 3 different types of authentication, but cannot get it to work.  Before I go too far with this, I just wanted to make sure what I'm trying to do is even possible, or if I should be looking in another direction, or if there's something I should be doing on my exchange server side of things to all this.

Any assistance is greatly appreciated, thanks!