To configure your mail account in Outlook Express, you need to follow
below mentioned guide lines

 1.  Start Outlook Express.

 2.  Select the Tools menu.

 3.  Select the Accounts menu item.

 4.  Select the Mail tab.
      The Internet Accounts dialog opens.

 5.  Click the Properties button.

 6.  Select the text box to enter your name choice for the mail server.

 7.  Select the E-mail address text box and change the e-mail address to:
        username@yourdomain.com

 8.  Select the Servers tab.
     a.  Select the Incoming mail (POP3) text box.
           Enter mail.yourdomain.com
     b.  Select the Outgoing mail (SMTP) text box.
           Enter mail.yourdomain.com

 9.  Select the Account name text box.
      Enter your account name as: username-yourdomainname

10.  Select the Password text box.
       Enter password.

11. Select the My server requires authentication check box.

12. Click the Apply button.
      Click the OK button.
      Click the Close button.

Your settings are complete!