Got a stage further, now have server accessing internet etc, pointing to wrong IP. I've also changed the host name to the same as FQDN and this has fixed that problem. Now only two small issue to resolve.
Could not find a host name that matches an IP address, and IP address '192.168.0.90' associated with host name mail.kennedysgroup.com in DNS cannot be confirmed as this hosts IP address.
Any ideas?