Well, obviously you have all the basic components in place, so it is not like you do not have the license or the software. Also, it seems like you understand what you are doing, so I guess I better ask: what is happening right now to your email?
Also, are you talking about outbound or inbound email? If it is inbound, then it is just a matter of setup, where you define your inbound VRP. I will try to help as much as I can, but I need you to tell me what and how things are setup right now.