Adding www. to domain name returns server not found error

[phoenix2gee]

Hi guys,
I host a .com domain name with cpanel, funny thing is that typing "http://domainname.com" shows my uploaded website but when i type "http;//www.domainname.com", i get a "server not found" error.

What could be the problem?
and how can i fix it so my site will show when a request for DomainName.com -- Reserve Your Place In Cyberspace with DomainName.com Domain Name Registration Services! is made.

my email address is info@afrointel.com.

Please help

[thewebhosting]

Please make sure that the CNAME record for www is exist or not?

[9techs]

Check CNAME as "thewebhosting" told on above statement.

you can check from WHM>>EDIT DNS ZONE or command prompt /var/named/yourdomain.com.db file

www 14400 IN CNAME yourdomain.com. (replace with your actual domain name)

if there is anything wrong make changes and restart the bind(named) service.