How to set your iPhone in DFU Mode
DFU (Device Firmware Upgrade) mode is not the same as restore mode. DFU mode bypasses the current OS installed and allows you to upgrade or downgrade your OS. If you are getting errors trying to restore in iTunes, DFU mode is very likely for you.
This is how to achieve DFU mode. You can do it on every iphone/ipod:
1. ***TURN THE VOLUME ON YOUR COMPUTER UP***
2. Open iTunes and connect your device yo your PC or Mac
3. Hold Power Button and turn off device
4. Hold Power + Home Button For 10 seconds
5. Let go of power button but keep pressing the home button for 10 seconds
6. When you hear the magical sound in itunes that your device is connected then and only then are you OFFICIALLY in DFU mode.iTunes will pop up a message telling you that it has detected an iPhone/iPod in recovery mode.
The iPhone screen will remain black like this:
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