iPhone 3G bb 6.15.00 running iOS 3.1.3

[StuFW4Real]

Hello,

I currently have a jailbroken (with jailbreakme.com and unlocked with ultransn0w 1.2) iPhone 3G on bb 6.15.00. I was wondering if it is possible to upgrade to 4.2.1 without changing the baseband or losing my unlock, as I am a T-Mobile user. The iPhone works fine as is, but I can't download many App Store apps running anything lower than iOS 4. It is also my understanding that the baseband I am on is required for T-Mobile. I DO NOT want to lose my unlock as I had spent three days jailbreaking and unlocking the darned thing. Thanks!

 

[Crystal-RX]

Hello,

I currently have a jailbroken (with jailbreakme.com and unlocked with ultransn0w 1.2) iPhone 3G on bb 6.15.00. I was wondering if it is possible to upgrade to 4.2.1 without changing the baseband or losing my unlock, as I am a T-Mobile user. The iPhone works fine as is, but I can't download many App Store apps running anything lower than iOS 4. It is also my understanding that the baseband I am on is required for T-Mobile. I DO NOT want to lose my unlock as I had spent three days jailbreaking and unlocking the darned thing. Thanks!

You can upgrade to 4.2.1 and that the latest fw for 3G. However, because you have Ipad baseband on yours, you must upgrade it by using customs firmware. You can refer to dev team blog where they addressed this issue previously.

 

[StuFW4Real]

Thank you. But one thing. Is custom firmware what redsn0w does when it jailbreaks, or is it a completely different download?

 

[Crystal-RX]

Thank you. But one thing. Is custom firmware what redsn0w does when it jailbreaks, or is it a completely different download?

It is completely different. Even you have customs fw on your phone, when jailbreaking with redsn0w, you still need to point it to the stock fw.

 

[StuFW4Real]

It is completely different. Even you have customs fw on your phone, when jailbreaking with redsn0w, you still need to point it to the stock fw.

Thank you! That was very helpful! I'm going to try it tonight. Hopefully I will be downloading the correct ipsw and i believe i'll need to put it in pwned dfu using redsnow to initiate it, but I think it'll be manageable. Thanks again!