http://<servername>/connectcomputer not working with windows Vista

I am trying to install my second Vista Business machine to an existing SBS
2003 Domain. I have tried all steps that I can find from forums, i.e.
Ensured that the SBS Server is the primary DNS, installed the patches on the
SBS (Basic) Box and the patch on the Vista Client. Turned off the Firewall
on the client. Ran Iexplorer as Administrator. Added the SBS Server and IP
to the Hosts file on the local PC....

Yet I still get the message box that starts:

"The Server that is running Windows SBS 2003 cannot be found. Verify the
following before you continue:......."

This is after I run nshelp.exe. There is a delay of about 20-30 secs, then
this box appears.

The first Client, I had to join to the domain manually, but I am not too
happy about doing this because of what else may not be configured correctly
by using the manual method.

Any help much appreciated.

Cheers

SS