By default WEBppliance for Windows uses the hostname to redirect to the control panel running on port 19638. If the hostname doesn't resolve then the redirect will fail. If you can add in an A record into your DNS server with the name of the WEBppliance hostname that resolves to the IP address of the server. If this is not possible then edit the files index.html and admin.html and change the hostname to the IP address of your server. What you should also do is right click on My Computer, click on Properties, Network Identification, Properties, More and then fill in the primary domain suffix. This will allow you to use the "Connect to Ensim WEBppliance control panel" shortcut on the Start Menu.