I might be wrong but looking at your question it seems that you have simply installed SmarterMail on a Windows Server without any proper configuration!
The (inbound & outbound) you are refering is due to the fact that e-mails from the same domain never leave the server unless otherwise configured.
There are many steps involved in setting up a proper e-mail server and more info is required, as @Heimir Eidskrem said previously.
Please feel free to contact me directly if you need any professional help.
Michael Gralke Augusto
Gralke Augusto - Business Communications
www.gralke-augusto.com