Forum Moderators: open
Sunny
[edited by: encyclo at 4:47 pm (utc) on Jan. 25, 2009]
[edit reason] no personal URLs please, see posting guidelines [/edit]
With many hosts, you can do it yourself with one click (yes, I choose my hosts carefully!)
:)
you should first verify that your dns configuration has www.subdomain.example.org pointing to the correct ip address and that your server at that ip address has been configured to direct requests to that virtual host to the correct document root.
If you want both versions working, you are wise to use a 301 redirect from www.subdomain.example.org to subdomain.example.org without the "www". This will avoid duplicate urls being indexed for the same content.