Will the server block my iPhone?

I've got my iPhone from the US, but I don't live there. Somebody told me that if I try to upgrade to iOS 7, the server might block my iPhone and it might just become a useless toy. I have never upgraded it before. I have no problem downloading Apps or using iTunes, and all of that. I'm just worried if it will block my iPhone. Please help me.
P.S: Do not give stupid answers like "Go and live in the States".
Thanks in Advance. Any help will be appreciated!

Nope. Nothing like that would happen if your iPhone is factory unlocked.