Apple TV, last generation, updated to latest firmware update at end of September and after update it came to a screen showing the iTunes logo and a picture of a cable below that. I could not move past that. Solution next:
Problem solved by buying a cable that is male regular USB on one end and other end is a male micro USB connector. The Apple TV has a female micro USB connector. First opened up iTunes on my PC then connected my Apple TV to the PC's USB input. I had my ethernet cable plugged into the Apple TV too, but no other cables besides that. The iTunes on my PC recognized the connected Apple TV and immediately gave me the menu option to Restore it (Restore puts on the latest firmware). I had my PC's iTunes do the Restore of the Apple TV. At the end of the process my PC's iTunes told me it had successfully completed the Restore of the Apple TV and advised me to disconnect the Apple TV from my PC then connect it back up to my TV set. All went well.
Apple store sells a small USB cable kit that has 3 short cables in the box, one of which is the micro USB to regular USB. Otherwise get your micro USB to regular USB cable at your computer store.