DFU mode is the last step on the iPhone, iPod touch, and iPad troubleshooting ladder.
Whether you want to jailbreak, un-jailbreak, update from an expired beta, or need a solution when nothing else is working, Apple has a solution for you: Putting you iPhone, iPod touch, or iPad into DFU (Device Firmware Update) mode can be your last, best hope for success.
As opposed to Recovery Mode, DFU mode puts the device into a state where it can still communicate with iTunes on Windows or Mac, but it hasn't activated the boot loader or iOS. This allows your iPhone, iPad, or iPod touch to be restored from any state. DFU mode requires a bit of timing and can take practice to get right, so if at first you don't succeed, don't be afraid to try and try again.
How to put your iPhone or iPad into DFU mode
- Plug in your iPhone, iPod touch, or iPad to your Mac or Windows PC.
- Make sure iTunes is running.
- Turn Off your iPhone, iPod touch, or iPad if it isn't already.
- Press and hold down the On/Off button on the right side (iPhone 6 or later) or top (all other iPhones, iPods, and iPads) of the device for 3 seconds.
- Swipe the slide to power off slider to the right.
- Press and hold down the On/Off button on the right side (iPhone 6 or later) or top (all other iPhones, iPods, and iPads) of your device for 3 seconds.
- Press and hold down the Home button on the front of your device while still holding down the On/Off button.
- Keep holding both buttons down for 10 seconds. (If you see the Apple logo, you've held them too long and will need to start again.)
- Let go of the On/Off Button but keep holding the Home button for about 5 seconds. (If you see the "Plug into iTunes" screen, then you've held it too long and will need to start again.)
- If the screen stays black, that's it! Your iPhone, iPod touch, or iPad should now be in DFU mode.
At this point, iTunes should show you an alert saying it's detected your iPhone, iPod touch, or iPad, and will allow it to be restored.
Reminder: If you see any logos on your device, you might be in Recovery Mode, but you're not in DFU mode. If Recovery Mode works, great. If not, try for DFU Mode again.