AT&T iPhone 4 - carrier unlock/jailbreak

[F6_Turbo]

Hi, apologies if this has been done to death.

I am currently visiting family in the subcontinent, and my cousin had an AT&T branded/sourced iPhone 4 32GB with iOS 4.2.1 given to her as a gift from the US.

Unfortunately she has taken it to all the local 'shops' and no one here seems to be able to unlock/jailbreak this, with the common response being "We can help you if it's a Verizon, but AT&T from the US, NO."

So she has been stuck using it as a glorified iPod. Is she doomed, or is there a way for her to actually use the phone?

Not very tech savvy myself, so thought I'd try my hand at asking the good people here....

 

[xfuz1on]

She will not be able to unlock her iPhone if it shipped with 4.2.1 as it would have an updated baseband. Only BB 1.59.00 is unlockable at this point.

 

[gray_mouse]

I'm sorta between n00b and exercising jailbreaker. I've jb my iphon4 with 4.0.2 fw and 01.59.00 modem. Now I have 4.3.1 fw and 01.59.00 modem. All works, except sob shows 1 bar.

Anyway, long story short. Download via google sn0wbreeze 2.5.1. Download .ipsw 4.3.1 for your iphone 4 (link given when you run the app). Upgrade it to 4.3.1 in baseband preservation mode. Then once done, go to phone options > about, and check and report back modem firmware version. If it's 01.59.00, then we good, if not, well you'd have to wait until lazy crackers break your modem fw.

I'm not clear if the above will downgrade your modem firmware, so we'll have to see or wait till someone answers.