The dev team has already advised users not to upgrade to iPhone OS 3.1 beta firmware. Both Geohot and Dev team have also advised users to save their iBEC and iBSS Signature Certificates of iPhone OS 3.0 for upcoming Jailbreak tools. Despite warnings, most of the users have updated their iPhone to OS 3.1 beta firmware (intentionally or accidentally) and now finding way to downgrade back to iPhone OS 3.0 firmware. It is important to note that, only iPhone firmware will be downgraded from 3.1 to 3.0 but not the baseband which ill remain 05.08.01.
- ITunes 8.2 installed on your computer.
- Original iPhone 3GS OS 3.0 Firmware.
Steps to Downgrade iPhone 3GS 3.1 to 3.0 OS Firmware
Step-01- Connect your iPhone to your computer using the USB cable.
Step-02- Switch off the device and put it in DFU. Follow simple instructions to put your iPhone in DFU mode- Click the ‘Home’ and ‘Power On’ button for 10 seconds and then release the power button only. iTunes 8.2 will display following window-
Step-03- Click on OK to continue.
Step-04- Click ALT (on keyboard) and ‘Restore’ (on iTunes) together and now select the original 3.0 firmware from your computer.
Step-05- Before doing the restore a confirmation message window will appear. Confirm by clicking ‘Restore’.
Step-06- A Restore Process will commence and at the end of restore process following error message “Unknown error occurred (1015)” from iTunes. Do not worry. You have not missed any step. Just click ok to continue.
Step-08- Extract the contents of the file “iRecovery-Mac.zip” on the desktop.
Step-09- Open application ‘Terminal’ (Applications> Utilities) and enter-
. / iRecovery-s
Step-10- Once you notice a Message entering in Recovery Mode, type following command
Step-11- Once the iPhone 3GS is rebooted, you can notice the ‘Emergency calls only’. Now wait till the iTunes is uploaded and reactivates your iPhone 3GS automatically.
Step-12- You can now restore a backup or configure the phone as “new.” with the iPhone Firmware 3.0.
Once you have downgraded your iPhone 3GS from 3.1 firmware to 3.0 firmware you can use purplera1n. Purplera1n (beta) is a free tool to Jailbreak iPhone 3GS running 3.0 firmware on windows and Mac. Read our articles on how to use Purplera1n to Jailbreak iPhone 3GS (Mac) and Jailbreak iPhone 3GS using Purplera1n (Windows). Use Ultrasn0w to unlock iPhone 3GS.