Apple TV 3 light blinking after update attempt, not working

Welcome to the Apple Community.

If your problem persists get yourself a micro USB cable (sold separately), you can restore your Apple TV from iTunes:

1. Remove ALL cables from Apple TV. (if you don't you will not see Apple TV in the iTunes Source list)
2. Connect the micro USB cable to the Apple TV and to your computer.
3. Reconnect the power cable (only for Apple TV 3)
4. Open iTunes.
5. Select your Apple TV in the Devices list, and then click Restore.

(You may already have a micro USB cable if you have a camera or other digital device)

I just wanted to say that unplugging the ATV from the power source for 30 minutes (not seconds) worked for me. I found the solution on another thread and it seems to be the solution for a few people.

Edit

Hi, I tried the software restore and update via Micro USB & power on my 3rd gen ATV and the light still blinks rapidly after iTunes indicated that the update was successful.