Open your web browser and type in:

http://mail3.webcentric-tn.com:8383
or
http://mail2.webcentric-tn.com:8383

depending on what mail server you are using. This will take you to the entrance of the web interface.Click on the Logon link.

Type in your mail admin name for the username. (ex. admin@yourdomain.com)
Type in your mail admin password for the password.

Click User Administration under the Administrative Account Options
drop-down box.
ClickAdd
Complete the fields accordingly.
UserID - This is the actual account name and is the address to which mail will be sent.