If you want to restrict the class so that it can only be seen by one particular external assembly, you use internal to limit the scope to the current assembly, and then you implement InternalsVisibleTo[^] to link this to the specific assembly.
*pre-emptive celebratory nipple tassle jiggle* - Sean Ewington
Which IP? Internal network? Public IP on the internet? "Localhost" is another name for 127.0.0.1, if one works, the other works. (Unless someone changed your HOST file)
From the network; check if firewalls are off, and try to fetch a blank HTML-testpage. Remember to set access-permissions in IIS.
If you are using local computer to access using ip address there should not be any issue only if DNS entry is set to redirect on another page. Secondly check if firewall stop your ip address from accessing the site ?
First try to simply add html page and check if it is also not working with ip address ?
Is you computer directly connected to internet?
May be you are using internet using a Router which has own LAN. In this case you cannot access it using IP but other computer in your local area network will be able to use with you LAN IP. Hope it helps.