I received an ATV2 for the holidays and its running 4.1 out of the box. I have been unable to save my SHSH files using Tiny Umbrella, I assume because Apple is no longer signing 4.1 SHSH blobss. This also means that if I try to install the custom 4.1 firmware I created using PwnageTool, iTunes won't allow me to install it correct?

I'm from what I understand from jailbreaking iPhones, I'll have to update to the newest firmware (4.2.1), and then jailbreak using my valid SHSH files. Is this correct? So, basically I should just wait until the DevTeam releases a untethered 4.2.1 JB, right?

Thanks.

Originally Posted by brs37

I received an ATV2 for the holidays and its running 4.1 out of the box. I have been unable to save my SHSH files using Tiny Umbrella, I assume because Apple is no longer signing 4.1 SHSH blobss. This also means that if I try to install the custom 4.1 firmware I created using PwnageTool, iTunes won't allow me to install it correct?

Correct. There are other in-place jailbreaking tools (redsn0w, greenpois0n, limera1n) but I don't think any of them offer a full-featured jailbreak for the ATV2 running iOS 4.1

Stay un-jailbroken on iOS 4.1 for now.. That's my advice.

Originally Posted by brs37

I'm from what I understand from jailbreaking iPhones, I'll have to update to the newest firmware (4.2.1), and then jailbreak using my valid SHSH files. Is this correct? So, basically I should just wait until the DevTeam releases a untethered 4.2.1 JB, right?

Correct.

Thank you.

Originally Posted by Olethros

Stay un-jailbroken on iOS 4.1 for now.. That's my advice.

I keep getting those annoying prompts to upgrade to the 4.2.1 firmware. Is there any reason not to update to 4.2.1?

Originally Posted by brs37

I keep getting those annoying prompts to upgrade to the 4.2.1 firmware. Is there any reason not to update to 4.2.1?

Really only AirPlay.
Apple - iPad - AirPlay

Thanks, but maybe I wasn't clear. I was wondering if there is any reason NOT TO update to the latest ATV2 firmware? Are there any advantages to staying at 4.1 without any saved SHSH files?

BTW, I noticed you're from Windsor Locks. I grew up in Winsted, CT.

Originally Posted by brs37

Thanks, but maybe I wasn't clear. I was wondering if there is any reason NOT TO update to the latest ATV2 firmware? Are there any advantages to staying at 4.1 without any saved SHSH files?

This is a hard question to answer.

Firstly, Apple has used a very strange numbering scheme with the firmware for the ATV.

The firmware is labelled as 4.1, 4.2 and 4.2.1 in the IPSW filename.

However the AppleTV itself reports these as 4.0, 4.1 and 4.1.1 when they are installed on the ATV2.

This has created some significant misconceptions and confusion.

I will use the IPSW numbering (as it is more consistent with the other iOS devices)

The initial shipments of ATV2 shipped with 4.1 (reported as 4.0) - pre-installed.

Only 4.1 can be jailbroken untethered (as far as I understand)

One thing that is not widely understood is that a partial SHSH is embedded in the firmware that is currently loaded on the device (whether it is a phone, iPad, iPod or ATV). In theory, if this partial SHSH could be extracted and used in conjunction with the limera1n bootrom exploit it would allow reflashing of this same iOS version (even if Apple had stopped signing restore requests for that iOS version).

Some iOS hackers are working on trying to make this theory reality. If possible it would be a powerful tool.

As soon as you update to the latest iOS version, the chance to extract this partial SHSH is lost forever.

However, this is all still theoretical and is not something to get excited about just yet.

Jailbreaking your device running factory iOS 4.1 should not destroy your chance to extract the partial SHSH. Only updating/restoring to 4.2.1 does that.

You need iOS 4.2 to get support for video airplay.

That's a summary of the status quo for the ATV2, what you decide to do is up to you.

Olethros, thank you. After saving my SHSH files this evening with TinyUmbrella, I have discovered that I am actually running the 4.2 software (8C510) so updating to 4.2.1 won't change anything based on your (great) explanation.

Looking forward to the next jailbreak!

Originally Posted by brs37

Olethros, thank you. After saving my SHSH files this evening with TinyUmbrella, I have discovered that I am actually running the 4.2 software (8C510) so updating to 4.2.1 won't change anything based on your (great) explanation.

Looking forward to the next jailbreak!

You lose the ability to (maybe) save a partial SHSH for iOS 4.2

How valuable the 4.2 partial SHSH may actually be long term I don't know.

4.2.1 includes minor bug fixes only