From being able to demo your iPhone or iPad on the TV to being able to view your photo gallery on the big screen, the Apple TV is a useful device — when it works. Sometimes, if you're having trouble updating or restoring your Apple TV, it's best to try entering recovery mode to get the job done. Recovery mode is just simple terms for DFU mode or device firmware update mode.
This basically means that in this mode, the Apple TV is able to communicate with iTunes to update or modify the software, but without loading any components that are meaningful to the end user. It's pretty simple, but requires a MicroUSB cable to connect the device to iTunes on your Mac or PC.
Pull out your trusty MicroUSB cable and connect the appropriate end to the Apple TV and the other to your computer's USB slot.
Note: Apple TV doesn't need to stay connected via HDMI to your TV or plugged into a power outlet for it to work. It's possible to connect it to iTunes while still connected to your TV, but to make your life easier, just unplug everything else from the Apple TV for now.
Launch iTunes if it doesn't launch automatically. Apple TV should appear as normal as any of your devices. Now is the time to restart it. Do it with the Apple TV remote; press and hold both Menu and Down simultaneously for about five seconds, then release. Note that the Apple TV disappears from iTunes.
When Apple TV restarts and you let go of the Menu and Down buttons, enter recovery mode (DFU) by holding down the Menu and Play Pause simultaneously for about five more seconds. Apple TV reappears in iTunes.
iTunes informs you that your Apple TV is in recovery mode. At this point, you have only two options:either eject the Apple TV from iTunes or restore it to its factory settings to fix any issues you may be having.
This step is optional. If you wanted to enter recovery mode just to waste time or prove to your pompous tech-savvy cousin that you're competent, congratulations, you made it and don't need to go any further!
However, if you're having issues with your Apple TV, it's worth restoring the software as a potential fix. With your Apple TV still connected, click Restore Apple TV… in iTunes. You should see a warning asking if you're sure you want to do this, as restoring the device will erase "all your media and other data". In addition, the latest available software update is automatically installed when restoring.
Click Restore and Update proceed. The process will take a few minutes, but does not require any further action on your part. When iTunes has finished restoring and updating Apple TV, it should exit recovery mode and enter its normal mode.
If not, disconnect the device from iTunes and reconnect it as a set-top box for your TV to ensure that you can now use it normally. Be sure to click Eject Apple TV in iTunes before unplugging it to safely eject it.