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I'm trying to downgrade from iOS 11 beta 2 back to iOS 10.3.2. I've downloaded the .ipsw from iOS 10.3.2 file from ipsw.me. After that, I've put my iPhone in DFU mode and plugged into my Mac (Sierra 10.12.5). iTunes detected the phone in DFU mode, so then I choose the restore option holding
option key and selected the .ipsw file downloaded. The iTunes pass through all process of restoring the phone, but right after it ends, the iPhone restart and go back to the DFU mode. I've tried to download the 10.3.1 ipsw version but the same problem occurred. I've no idea how to proceed.