Need Unlock help for 3G (GF uses T-Mobile and wants my 3G)

[Memphis88]

I just got my iPhone 4 and my girlfriend (who has T-Mobile) wants my old 3G. I don't have any clue about what to do or how to do it when it comes to unlocking the phone so I would appreciate yalls help. I'm also wondering if it will it affect my iPhone 4, warranty, or anything else if I unlock the 3G and give it to her? Any advice y'all can give me is greatly appreciated!

 

[Imsuperjp]

You should spend an hour or so reading through all he threads as this has been discussed numerous times and so you known what issues others have ran into. I think this biggest issue people have is just reading one thing and thinking it is the right way and then screw their phone up. For my 3G, I used redsn0w to jailbreak and ultrasn0w to unlock

 

[CKtoph]

I understand how you feel with so many threads and trying to find answers.

This thread has a great flow chart that will answer your question.

https://forums.macrumors.com/threads/942632/

 

[Memphis88]

Thanks for the help guys.