How to Go Back to iPhone 2.1
- 1). Go to the iPhone OS 2.1 IPSW (see Resources) program and click "Open With."
- 2). Connect your iPhone to your computer via USB cable. This should automatically launch iTunes.
- 3). Turn off your iPhone.
- 4). Hold the "Power" button and the "Home" button on the iPhone at the same time for 10 seconds.
- 5). Release the "Power" button but continue holding the "Home" button. iTunes will push the phone into DFU mode.
- 6). Go to your computer and hold down the "Alt" key and click "Restore" in iTunes.
- 7). Open the IPSW file and your iPhone will reboot with the 2.1 OS system in iTunes.
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