I think there are many people accidentally delete or format theirTV hard drive (like I did). Obviously we need to buy a new hard drive or restore damaged hard drive to the functional state. There are many thread regarding this subject on over internet, but I think my method is simplest and easiest. Here is what I did.
1. Get the latest TV image from link below
2. Connect your hard drive to your Mac.
3. Open the Disk Utility application. You should see new firmware that you just downloaded and TV and see your new connected hard drive.
4. Click on your new hard drive and go to restore tab.
5. Drag firmware to the ‘source’ field and new hard drive to the ‘destination’ field, as in picture below.
6. Click on restore and you’re done.
PS. This method is working on my machine which I spent less than 10 minutes for the whole process. However, there is no ‘recovery’ partition created on this method (which is not important since everything on my AppleTV take 2.0.2 is working fine)