from Google webmaster tools:
what does that mean exactly and what should I do? it's a friends site.
A website is located on a specific computer that is hard wired to the Internet... you website is located in some folder in the system and the computer's owner associates an IP address to correspond to that folder.
At the registrar you edit the DNS to indicate the system the website for your domain in on and when any requests go out for users/visitors the registrar serves up the system (computer) where your website is and when the system receives that request it serves up the folder when the website is factually located to the user/visitor.
1. the DNS address is set incorrectly at the registrar.
2. the owner set the location of your website incorrectly.
3. The system where you domain resides is down/off
4. sometime (but rarely) the registrar is down.
Stupidity isn't another form of knowledge!