Beste antwoord door Kaassausje
It's the region lock preventing you from using the phone with a non-European simcard. You need to make a phone call with an European sim card (about five minutes should do it). If you don't do that, the phone simply won't connect to any non-European network.
There should've been a sticker on the box in which your phone came, the sticker states that you can use European simcards only, unless you unlock the phone by using it. If you'd like to read more about this, I suggest this article.