problem with mapping a domain on new site - all settings seem ok it just doesn't seem to work

Hi Support,

having problem with one domain name (but not 8-7 others on my network that are working ok)

white-horse-forge.couk is the new domain mapped I've changed the dns servers to my server. added the ip address to the domain mapping config screen and I've deleted the code recommended on that site in the wp-config.php . Not sure of any other settings I need to do - i've double checked the domain reg interface and the name servers are correct. Any ideas if it is wordpress or any other settings. i have deleted twice and re-added the domain name in the the particular site. Is there another way to do this.