[DotNetDevelopment] How to get port number

[Gourav]

Hi All,
     Actually i made a small application in ths mail send to the
user....
But in this i didn't know that what is the port number of my
server..then can anyone tell me how i get the port number of my mail
server...
currently i am using
http://www.mail2web.com

for open my email...then please tell me how i get the port number of
http://www.mail2web.com server......