SBS 2003 Client Connect Wizard

I am having a lot of trouble setting up a new server - can't run Client
Connect Wizard on any clients.

I type "http://server/ConnectComputer" in Internet Explorer and hit go. The
process hangs with "opening page ..." in the status bar.

SBS std is set up on our only server, which is also our DC, DNS, DHCP
server. The device has two NICs - setup as one for external connection and
one for local. Both are poiinting at this server for DNS and forwarders are
setup to our ISP.

Clients all run XP Pro.

I can ping the server from all clients.

All clients can use the internet with no difficulty.

Any help will be gratefully received. Thanks in advance.