My ATV has been sitting for a few months in its box while I gathered the time to go through the jailbreaking process.
Because that gave me time to look over everything, I figured first thing I would do is use TU to save SSH. But TU wouldn't save the SSH. It gave the log messages:
05/07/2011 23:27:16.095 This device isn't eligible for the requested build.
05/07/2011 23:27:16.102 CYDIA DOES NOT HAVE YOUR SHSH FOR AppleTV 4.2.1 (8C154) THERE IS NO WAY FOR YOU TO GET THEM. SORRY. YOU ARE JUST TOO LATE.
05/07/2011 23:27:27.814 CYDIA DOES NOT HAVE YOUR SHSH FOR AppleTV 4.3 (8F191m) THERE IS NO WAY FOR YOU TO GET THEM. SORRY. YOU ARE JUST TOO LATE.
It dawned on me that maybe CYDIA wanted me to upgrade the ATV—perhaps it needed to have the SHSH for ATV 4.3 before I began, but I couldn't figure out how to upgrade that, so I decided to go directly to SeasonPass.
Download went fine, however, when I got to the iTunes reset, (It did give me a success message I got the following very unpleasant message
The Apple TV "Apple TV" could not be restored. This device isn't eligible for the requested build.
Again, wondering if I had an outdates iOS, I attempted to restore the ATV to what the latest updated version. However, I got the same message (The Apple TV "Apple TV" could not be restored. This device isn't eligible for the requested build.) here too.
Does this mean that the ATV is bricked? It sure seems so.
Then I used SeasOnPass to do the jailbreaking for me. When it asked to enable scripting, I enabled it. Unfortunadly iTunes doesn't get the message, the new .IPSW doesn't get installed.
After some searching, I read about how TinyUmbrella.app could make it possible to restore to the original aTV. Here I get the same message as you Bromo!
CYDIA DOES NOT HAVE YOUR SHSH FOR AppleTV 4.2.1 (8C154) THERE IS NO WAY FOR YOU TO GET THEM. SORRY. YOU ARE JUST TOO LATE.
After that I thought maybe I could try to install the .IPSW by hand, using iTunes, press 'alt' and the recover. iTunes asked me for the file location, so far so good.
The uploading didn't last very long (much shorter than 10min). The conformation that Apple I said oke, but Apple answered that it couldn't be done (This device isn't eligible for the requested build).