How to put an iPhone into DFU mode
There are a lot of issues that can be solved on your iPhone by restoring the device. Like software glitches, forgotten password or you just want to start fresh. So we will explain how to do it.DFU or Device Firmware Upgrade mode allows all devices to be restored from any state.To enter you iPhone, iPad, or iPod into DFU mode you "
Plug the device into a computer with a USB cable and the itunes application open
Turn off the device
Hold the Power button for 3 seconds
Hold the Home and Power buttons for 10 seconds
Release the Power button but keep holding the Home button
After about 15 seconds you will see that iTunes has detected a device in Recovery Mode
The devices screen should be black with no logo or image. Now you can click restore in itunes to begin the restore process.To exit recovery mode, hold the power and home buttons together until the Apple logo appears.