Open Mozilla Mail window, either by clicking on its icon from menu or by clicking the Mail & Newgroups icon on the lower left part of Mozilla web browser window.

Click on Edit and then Mail & Newgroups Account Settings.

Click Add Account. On the first screen select Email account and then click Next.

Specify your name in the Your Name field and your email address in the Email Address field. Click Next to continue.

On the next screen you can choose POP or IMAP depending on whether you want to use POP or IMAP. You also need to specify 'pop.example.com' or 'imap.example.com' (replace example.com with your own domain name) in the Incoming Server field. Click Next to continue.

Specify your full email address in the User Name field. Click Next to continue.

Specify a descriptive name for this account, for example 'My Email Account'. Click Next and then Finish to continue.

Now you should be taken back to the Mail & Newsgroups Account Settings menu. Click on Outgoing Server (SMTP).

Specify 'smtp.example.com' in the Server Name field. You also need to specify '8025' or '587' in the Port field and specify your email address in the User Name field.

Click OK to finalize the settings.