Did you just jailbreak and unlock your iPhone 3GS only to accidentally destroy all your hard work by pressing the update button? Stuck in an endless loop of 1015 error messages and inescapable recovery mode? Fear not! I have found the answer…
Read the instructions in full before trying the steps.
Disclaimer: This guide for educational purposes only. So, try it at your own risk. I can NOT be held responsible if anything goes wrong. Please read through the instructions before implementing.
Download iOS 4.1 (iPhone2,1_4.1_8B117_Restore.ipsw)
Step 1. Plug in your iPhone and launch iTunes and RecBoot.
Step 2. In iTunes, Press and hold Option and click on the restore button. This will allow you to choose the iPhone2,1_4.1_8B117_Restore.ipsw file as your firmware.
ATTENTION: iOS 4.1 will update your baseband which is not reversible. It will void your warranty, and you will not be able to update or recover the phone to any other iOS.
Step 3. Let iTunes and the iPhone go through the sequence. They will still display the 1015 error message, but this is not a problem.
Step 4. In RecBoot, press the Exit Recovery button. This will bring your iPhone to a Emergency State… where you still see the “connect with iTunes” image on your iPhone screen, but you would be able to make emergency calls.
Step 5. Launch RedSn0w.
Step 6. Click Browse, and choose the iPhone2,1_4.1_8B117_Restore.ipsw as the file you want to use. If your iPhone is of the new OS (most likely, yes) confirm it.
Step 7. Now select your desired options. Make sure that at least Install Cydia is selected. Now hit Next button.
Step 8. RedSn0w will ask you to turn off your device. Hold down the Power button until the red slider comes on and turn off the phone. When it’s off and plugged in, hit the Next button.
Step 9. Follow the on screen instructions. At this point it may simply go through the sequence, but in case it doesn’t you’ll be instructed to put your device into DFU mode.
On iPhone hold down Power button for 3 seconds,
without releasing Power button, hold Home for 10 seconds,
without releasing Home button, release Power button and hold Home button for 30 seconds.
Step 10. Once your device goes into DFU mode, RedSn0w will start jailbreaking it. Once done, you can find the Cydia icon on your iPhone 3G home screen.
You should be fixed, out of the loop and done. If you want to re-Unlock your phone simply follow these instructions.
Whatever you do after this, just make sure not to press the update button when you plug in your iPhone, or else you’ll have to go through these steps all over again.