Email notification using my smtp mail server

I am sorry people I am having with mail on my OJS 3.0.0.1. I want to use my smtp mail server for sending email to people who has subscribed to the journal. But i see that those emails are not sent back to users.
I have set the config.inc.php to use my smtp mail server and added a user name and password but it is not working. How to i resolve it.
Please help me