Atlast I can send mail thru my Outlook. Our webhost changed the port to 26. I can now send and receive.
There are lot of ISP that closed this port due to spam. As a way of protecting their servers and infrastructure they deny access on this Port. When we are having problem with our mail server I called the Webhosting support. I told him that I can’t do a telnet on my mail server with the port 25.
He quickly replied to me. use port 26. then Voila i can send email even at home.