This is an error you get from iTunes when you try to access the iTunes store or when you first start up iTunes to log in with your credentials. This is probably because there is no network connection obviously. But it was different in my case.
I connect to the network through a proxy server. So I have to configure my internet that way in the internet options. This would become my default system settings. But, I can also configure it only in Firefox or Chrome alone and I can still browse the web through the proxy server.
Change the proxy settings in ‘Internet Options’ , which can be found by searching for it in the search bar in win7. It is also the default internet settings in Internet Explorer. As soon as that was cleared iTunes was able to connect to the iTunes store.
If you don’t connect to the internet using a proxy server then,
1. Check your internet connection. Open your browser and see if you can go to any web page.
2.Check if there are any firewalls that is configured to not allow packets from iTunes.