shart & all,
I am getting the same problem installing ISPConfig.
When it prompts for
Please enter the domain (e.g. xyz.de):www.mydomainname.com
then I get ERROR: The URL is not reachable! The installation routine stops here!
When I checked for the suggested solution the file
does not exists yet.
How did you get the installation working?
What are the valid values for the domain name?