Kan ikke få IIS til at virke

Hej.

Jeg får denne fejl:

While trying to retrieve the URL: http://localhost/

The following error was encountered:

Unable to determine IP address from host name for localhost
The dnsserver returned:

Name Error: The domain name does not exist.
This means that:

The cache was not able to resolve the hostname presented in the URL.
Check if the address is correct.

hvad er der galt?

thomasu