How to Change Bootloader Firmware on iPhone
- 1). Turn on your iPhone and connect it to your computer with the USB cable. Click the iTunes shortcut on your computer desktop, Start menu or OS X dock to start the program.
- 2). Hold down the iPhone's "Power" button and the button below the screen down for precisely 12 seconds. After 12 seconds, keep your finger on the power button, but release the button below the screen. Release the button when the screen turns off.
- 3). Click "Restore" when the iPhone update window appears in iTunes. Hold down the "Alt" key on your keyboard (Mac users hold down the "Option" key) and click "Restore" again.
- 4). Navigate to the folder where the bootloader file you wish to install is saved. Click the bootloader file, then click "Open." Wait for the installation process to complete. When your iPhone displays the standard lock screen, it's safe to remove the phone from the USB cable.
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