Need to unlock iPhone for sale

[trainwrecka]

I sold my iPhone 3G on eBay, and after the guy won he asked if I could unlock it for T-Mo for him. I know how to do it while it is activated under my account, but have no clue how to unlock for his use. I'm not even sure what version of the firmware it's running.

I was running the most recent version, then I went into settings and chose "Erase Content & Settings" to wipe the phone. I would assume it would still be running 3.1.3.

If I connect the phone to my computer it asks for a SIM, I insert a SIM, and then it wants to sync it to my computer (either as my old iPhone or a new one).

Any help (or links to how to do this) would be greatly appreciated!


---- EDIT -----
Also, does it matter if I setup on a Mac as to what computer he has? Mac or PC?

[michal2648]

go into settings , general and about something like that and see what firmware you have, but if you upgrated to the newest one you probably won't be able to unlock, just go to cydia and download fuzzyband and then run it see what it says.

[trainwrecka]

I'm on version 3.1.3 (7E18) and Carrier AT&T 5.6

[bbgt2]

If you are on 3.1.3 you will not be able to unlock unless you were unlocked before and Cydia has your 3.1.2 SSH files.

[ohusman]

you can use Spirit to jailbreake and use redsnow for carriaer unlock.

[trainwrecka]

I was afraid of that. Thanks ohusman for a possible solution, and thank you everyone else for responding so quickly.

[iYeow]

I was afraid of that. Thanks ohusman for a possible solution, and thank you everyone else for responding so quickly.

Redsn0w is not an unlock tool, your Iphone is locked at version 3.1.3, you can only jailbreak and only use it on AT&T carrier from now on until a new unlock comes out........

[lefti]

Redsn0w is not an unlock tool, your Iphone is locked at version 3.1.3, you can only jailbreak and only use it on AT&T carrier from now on until a new unlock comes out........

This is a true story. If you are already on 3.1.3, you can not unlock it. Don't spin your wheels for no reason.