I'd like to know if it's possible to activate an AT&T iPhone 3GS outside of USA.
I live in Brazil and I've bought this iPhone from eBay. As it came with iOS 4.x (I don't remember the exact version), the first time I connected it to my computer (Mac), iTunes offered to upgrade it to iOS 6.1.3.
This is the problem: it was jailbroken before the upgrade and it was working fine with my carrier (TIM). But after the upgrade, I'm not able to activate it.
Even if I try to "hacktivate" and install ultrasn0w, it still doesn't recognise my SIM card.
I've read somewhere that I should use an AT&T SIM card to activate it and then I should jailbreak and install ultrasn0w.
And this is my question: Will this process work if I do it in Brazil? I mean: I'm planning to ask a friend to bring me an AT&T SIM card from USA. Would this work as expected? Or does the iPhone must be in USA for the activation?
Settings > General > About > Modem Firmware
Settings > General > About > Serial Number