Hi there,

I have been jailbreaking/unlocking since the original iphone came out and this is the first time I have had an issue. I really could use someone's help cause I just sold my phone on ebay and I need to ship it to the guy soon. This all started when I was resetting my phone settings and deleting my personal info on the phone. Its a 3GS with the newer bootroom. I was at 4.2.1 cooked with pwnage and tethered jailbroken with redsn0w and unlocked with ultrasn0w at baseband 5.12.01. Everything worked fine till i was getting ready to ship it and reset all settings and wiped the phone. after the reboot i was stuck at the apple logo. So I went into DFU mode and tried to restore with a custom 4.2.1 firmware. It would fail. I would get error 1600. I read somewhere that starting with 4.2.1 that once you put it on and jailbreak it, you can't put it on again. I am not sure if its true. Anyways, I tried restoring in recovery mode and no luck. I tried rejailbreaking it with redsn0w but it would stall at "installing bundles". So I tried downgrading to and standard 3.1.2 firmware and it worked. from there I once made back to a custom 4.2.1 but when I tried to jailbreak with greenpois0n, it crashed my and my phone was back in recovery loop and I couldn't restore again to 4.2.1. I was able to go back down to 3.2.1 tho. so that is where i am at now and every time i try to restore with a cooked 4.1. or 4.2.1 firmware, i get a error 21 in itunes and I need to use tinyumbrella to kick it out of recovery mode afterwards.

Does anyone have any idea what happened and how can I get this phone back to 4.2.1 without upgrading the baseband so I can eventually unlock and jailbreak the phone again? I really could use someones help here. Im pretty experienced so quick solutions are fine. I can't afford to refund the money to the buyer either. Thanks to anyone whiling help. Seriously.

Originally Posted by orbitalpunk

I have been jailbreaking/unlocking since the original iphone came out and this is the first time I have had an issue. I really could use someone's help cause I just sold my phone on ebay and I need to ship it to the guy soon. This all started when I was resetting my phone settings and deleting my personal info on the phone. Its a 3GS with the newer bootroom. I was at 4.2.1 cooked with pwnage and tethered jailbroken with redsn0w and unlocked with ultrasn0w at baseband 5.12.01. Everything worked fine till i was getting ready to ship it and reset all settings and wiped the phone. after the reboot i was stuck at the apple logo. So I went into DFU mode and tried to restore with a custom 4.2.1 firmware. It would fail. I would get error 1600. I read somewhere that starting with 4.2.1 that once you put it on and jailbreak it, you can't put it on again. I am not sure if its true. Anyways, I tried restoring in recovery mode and no luck. I tried rejailbreaking it with redsn0w but it would stall at "installing bundles". So I tried downgrading to and standard 3.1.2 firmware and it worked. from there I once made back to a custom 4.2.1 but when I tried to jailbreak with greenpois0n, it crashed my and my phone was back in recovery loop and I couldn't restore again to 4.2.1. I was able to go back down to 3.2.1 tho. so that is where i am at now and every time i try to restore with a cooked 4.1. or 4.2.1 firmware, i get a error 21 in itunes and I need to use tinyumbrella to kick it out of recovery mode afterwards.

Does anyone have any idea what happened and how can I get this phone back to 4.2.1 without upgrading the baseband so I can eventually unlock and jailbreak the phone again? I really could use someones help here. Im pretty experienced so quick solutions are fine. I can't afford to refund the money to the buyer either. Thanks to anyone whiling help. Seriously.

Restore logs please: http://www.hackint0sh.org/f137/130802.htm

Some tips...
DFU mode is not enough for custom 4.2.1 or 4.1 IPSW, you need to be in pwned dfu mode (you need to go through the process of making a custom IPSW and then follow the prompts to put the phone into DFU mode, tnen pwnagetooll sends the correct payload to PWN DFU.
Also Redsn0w on windows has a "enter pwned DFU mode" option.
Once you are in pwned DFU mode, and iTunes 10.1 can contact either gs.apple.com or Saurik's server or a local TSS server to get a 4.2.1 SHSH, then the restore should succeed.

Prior to the discovery of the limera1n exploit (and it's implementation as a paylod for pwned DFU mode) - it was not possible to restore custom IPSW on the new bootrom 3GS.

For new bootrom 3GS, until Pwnagetool is updated to include the new Feedface exploit used in the current version of greenpois0n. You will need to do a two-step process.

Firstly, you need a very barebones 3GS pwnagetool bundle/ipsw. You cannot hacktivate, include ultrasn0w or Cydia in your custom IPSW.
The only real thing the custom IPSW does is load 4.2.1 with a patched ramdisk that prevents baseband update.

Then you should jailbreak with greenpois0n. Finally, as greenpois0n does not include hacktivation (yet). Run redsn0w 0.9.6 rc8 and select "install Cydia" only. This will hacktivate.
Then you can install ultrasn0w from Cydia and unlock.

You are a true savior Olethros. This totally worked! It was the pwn dfu that made the difference. I think pwn dfu is really important for dev team to mention. It's not nearly mentioned enough. Anyways, everything works now. 4.2.1 jailbroken with greenpoison and unlocked with ultrasn0w.

Thank you thank you again Olethros.