iPhone Help trying to use Softbank iPhone (Japan) 4s 5.1.1 baseband 2.0.12 on AT&T(USA)

Discussion in 'Jailbreaks and iOS Hacks' started by audiotronica, Aug 17, 2012.

  1. audiotronica macrumors newbie

    Joined:
    Mar 3, 2009
    #1
    Hi, I couldn't find the answers in a search so I'm writing here. I have an iPhone 4S purchased in Japan from Softbank carrier (black sim card). I am living in USA now and have a plan with AT&T. If I try and use AT&T's sim card, I was unable to authorize the phone. Now I can enter the sim card, but it will say Searching..., No Service, or Invalid PIN. Is there any solution for me? Do I need a Gevey or R-Sim-III 3? I am I just out of luck?

    Will this process work? http://www.youtube.com/watch?v=YonFx8xXBKo


    Phone is modem firmware baseband 2.0.12
    Version 5.1.1 9B206

    Thank you for the help and sorry for the redundance.
     
  2. noiceT macrumors 6502a

    Joined:
    Jul 7, 2008
    Location:
    Catalina Wine Mixer
    #2
    You need to unlock the phone. Gevey or imei unlock. The imei unlock thread in this forum has some promising results.

    http://forums.macrumors.com/showthread.php?t=1398957
     

Share This Page