ITunes could not complete iTunes Store request.

I have checked my Internet connections and everything is working just fine. The problem is iTunes because is not working due to network connection. This is my first version of iTunes and also the first time when I want to use to connect with my iPad Mini. Why the iTunes cannot connect to the Internet ?
My Internet connection is working just fine.
Thank you !

We could not complete your iTunes Store request. The network connection could not established.
