Well I sold my unlocked and jailbroken 3G iPhone running 4.1 on craigslist the other day.. I was using it until I sold it, so when I gave it to him I "erased all data and settings" about an hour later he had called me saying its stuck on the pineapple.. So I refunded him his money and took the iphone back hoping I could fix it and re-sell it clean. Well... not exactly going as planned.
I originally tried doing the restore with the same jailbroken 4.1 - but it wouldnt work.. a buddy of mine told be apple wasn't signing the 4.1 anymore on iTunes so I used pwnage to build a custom 4.2 firmware. I'm now getting a 1015 error right before the restore is finished. And now the phone is stuck in recovery mode.. but I CAN get it into DFU, nothing else.. not even the stuck pineapple anymore.
Downgrade it to 3.1.3. Run Redsn0w 0.9.4 (point at the 3.1.2 ipsw) and select enter pwned DFU mode only. Then when it's in pwned DFU, shift+restore to the custom 4.2.1 ipsw. If you'd rather keep it at 3.1.3, simply do the redsn0w thing as well except also select Cydia to jb.
Edit: don't select pwned DFU if you are keeping it at 3.1.3. Just select Cydia.
Last edited by i.Annie; 12-26-2010 at 05:29 PM.
Reason: Automerged Doublepost
If you have installed ipad baseband, you can either restore to stock 4.1 fw ( if you have 4.1 shsh blob) or restore to custom firmware of 4.2.1 (in your PM ).
When you receive it, rename .zip to .ipsw and use redsn0w 0.9.8b6 to put you into dfu mode and then restore to this file .