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zen

macrumors 68000
Original poster
Jun 26, 2003
1,713
472
I've had a long look through the forum but I'm a bit confused - is there any way to downgrade my iPod touch from iOS4 if it hasn't been jailbroken? My iPod is practically unusable in iOS4, with major lag on everything.

I've tried downloading the 3.1.2 and 3.1.3 firmware and putting the iPod into restore mode, but iTunes just says the firmware cannot be applied.
 

Skyhigh223

macrumors regular
Jul 21, 2009
151
0
All new iDevices (iPhone 3GS, iPhone 4, iPod 3G, and iPad) have to have special 'SHSH' signatures from Apple to allow them to install firmwares. If apple doesn't offer a SHSH signature for a version of a firmware, then you cannot downgrade no matter what.

Older devices like your 2G iPod don't normally check for SHSH signatures from apple, so you can load pretty much any firmware you like onto them.

However, iOS4 introduced 'soft' SHSH checks for older devices, meaning that older devices that upgraded to 4.0 need a SHSH signature from Apple. Since you've already upgraded to 4.0, your device is now checking for SHSH signatures when you try to restore.

Since apple doesn't offer SHSH signatures for iOS3.x anymore, you're stuck on iOS4. There is no way to downgrade.

You can back up your SHSH signatures using FirmwareUmbrella (Google it). You don't have to be jailbroken to use it. It creates a copy of your signatures for the iOS version apple is currently signing, which allows you to restore if or when you need too. You're too late to backup your signatures for 3.1.3, so you might as well backup signatures for 4.0 so you can restore to it if 4.1 is even worse. :)

Oh, BTW, I'm on a 2nd Gen iPod with iOS4, and my iPod is running perfectly. Maybe restoring and setting up as a new iPod rather than restoring from a backup will help?
 

zen

macrumors 68000
Original poster
Jun 26, 2003
1,713
472
All new iDevices (iPhone 3GS, iPhone 4, iPod 3G, and iPad) have to have special 'SHSH' signatures from Apple to allow them to install firmwares. If apple doesn't offer a SHSH signature for a version of a firmware, then you cannot downgrade no matter what.

Older devices like your 2G iPod don't normally check for SHSH signatures from apple, so you can load pretty much any firmware you like onto them.

However, iOS4 introduced 'soft' SHSH checks for older devices, meaning that older devices that upgraded to 4.0 need a SHSH signature from Apple. Since you've already upgraded to 4.0, your device is now checking for SHSH signatures when you try to restore.

Since apple doesn't offer SHSH signatures for iOS3.x anymore, you're stuck on iOS4. There is no way to downgrade.

You can back up your SHSH signatures using FirmwareUmbrella (Google it). You don't have to be jailbroken to use it. It creates a copy of your signatures for the iOS version apple is currently signing, which allows you to restore if or when you need too. You're too late to backup your signatures for 3.1.3, so you might as well backup signatures for 4.0 so you can restore to it if 4.1 is even worse. :)

Oh, BTW, I'm on a 2nd Gen iPod with iOS4, and my iPod is running perfectly. Maybe restoring and setting up as a new iPod rather than restoring from a backup will help?
Well, cock-a-doodle-doo. Thanks Apple.

When I restored it I did it from the backup... so I'll try setting it up as a new iPod. Thanks for the tip!
 

tadad1

macrumors 6502a
Oct 20, 2008
638
82
Just to clarify a couple of the points raised by Skyhigh223,

Older devices like your 2G iPod don't normally check for SHSH signatures from apple, so you can load pretty much any firmware you like onto them.

Correct with the exception of the current 8GB MC model which is a 2nd gen but has the new bootrom which does require signing by Apple when restoring so can not be downgraded unless you have your SHSH blobs backed up for the version firmware you are downgrading to.

However, iOS4 introduced 'soft' SHSH checks for older devices, meaning that older devices that upgraded to 4.0 need a SHSH signature from Apple. Since you've already upgraded to 4.0, your device is now checking for SHSH signatures when you try to restore.

Partially correct, however on the original pre 2009 release MB model 2G touch the soft SHSH checks only apply to 4.0 and future releases so for example if you updated to 4.1 you could not go back to 4.0 unless you had your SHSH blobs for 4.0 backed up. You can however still go back to 3.1.3\3.1.2 or earlier.
 

zen

macrumors 68000
Original poster
Jun 26, 2003
1,713
472
Partially correct, however on the original pre 2009 release MB model 2G touch the soft SHSH checks only apply to 4.0 and future releases so for example if you updated to 4.1 you could not go back to 4.0 unless you had your SHSH blobs for 4.0 backed up. You can however still go back to 3.1.3\3.1.2 or earlier.
Hang on, I have an original release 2G iPod touch (8GB). Are you saying I *can* go back to 3.1.3?
 

tadad1

macrumors 6502a
Oct 20, 2008
638
82
Hang on, I have an original release 2G iPod touch (8GB). Are you saying I *can* go back to 3.1.3?


Yep.

Quote by MuscleNerd of the DevTeam

Those of you with jailbroken iPhone3G and ipt2G devices may now have noticed Cydia starting to save your SHSH blobs too, just like it does for iPhone3GS, ipt3G and later devices. That’s because starting with 4.0, Apple started putting a “soft” SHSH blob check in the firmware. The SHSH blob check is very real in the sense that if iTunes can’t get your blobs (because the Apple signing window has closed), the iTunes restore will error out. But it’s “soft” in the sense that those devices can always use redsn0w or PwnageTool to get past the error (the bootroms themselves for those devices don’t require blobs to be in the firmware files, unlike the newer bootroms). Furthermore, since the 3.x IPSWs for these devices don’t enforce it, you can always restore to 3.x IPSWs outside of any signing windows.
 

TBi

macrumors 68030
Jul 26, 2005
2,583
6
Ireland
Hang on, I have an original release 2G iPod touch (8GB). Are you saying I *can* go back to 3.1.3?

Why don't you back up your iPod, download 3.1.3, stick the iPod in DFU mode (google it) and do a restore (alt+click and select the file).

See what happens. It will either work or won't work. Come back and let us know.
 

zen

macrumors 68000
Original poster
Jun 26, 2003
1,713
472
Except this doesn't work, like I said.

I download the 3.1.3 or 3.1.2 firmware from http://www.felixbruns.de/iPod/firmware/

Put the iPod into restore mode, plug it in, option-click restore in iTunes so I can select the firmware, but iTunes throws me out when it says it is verifying the iPod. Like I said in my original post.

Is there some other method I should use?
 

TBi

macrumors 68030
Jul 26, 2005
2,583
6
Ireland
Have you tried DFU mode? It's different from restore. You may have to use redsn0w or pwnage tool.

Dev Team says there shouldn't be a problem on your device.
 

zen

macrumors 68000
Original poster
Jun 26, 2003
1,713
472
Doesn't work. iPod in DFU mode, option-click restore to select the 3.1.3 firmware, goes to verify with Apple, says "The iPod "iPod" could not be restored. This device isn't eligible for the requested build."
 

tadad1

macrumors 6502a
Oct 20, 2008
638
82
Not sure what the problem is then but if your touch is an MB model it is nothing to do with SHSH blobs. I just tried it to be sure and had no problems. Was running iOS 4.0 jailbroken, downloaded 3.1.3 from felixbruns, put my touch into recovery mode (with the iTunes connect logo showing), shift+restore to 3.1.3.ipsw on my desktop and it downgraded without a hitch.
 

TBi

macrumors 68030
Jul 26, 2005
2,583
6
Ireland
Doesn't work. iPod in DFU mode, option-click restore to select the 3.1.3 firmware, goes to verify with Apple, says "The iPod "iPod" could not be restored. This device isn't eligible for the requested build."

Ok well use pwnage tool or redsn0w. They load the ipod directly, i think.
 

zen

macrumors 68000
Original poster
Jun 26, 2003
1,713
472
Does my iPod have to have been jailbroken to start with to use those?
 

devils punchbow

macrumors member
Feb 12, 2010
62
0
I've had a long look through the forum but I'm a bit confused - is there any way to downgrade my iPod touch from iOS4 if it hasn't been jailbroken? My iPod is practically unusable in iOS4, with major lag on everything.

I've tried downloading the 3.1.2 and 3.1.3 firmware and putting the iPod into restore mode, but iTunes just says the firmware cannot be applied.

You want to reverse to a older version firmware on your touch ? This sort of thing is not supported by Apple, but this is how it can be done......

I did this recently. It was easy. Though 3.1.3 did not work for whatever reason. 3.1.2 did work properly. I made the mistake of using 4.0 as well.

First you need a copy on your computer of the firmware file you want to install on your touch. Download that from here.....http://www.felixbruns.de/iPod/firmware/

Then follow these steps. It pretty easy.......http://lifehacker.com/5572003/how-to...s-4-to-ios-313

You'll be out of 4.0 in no time.......my touch is not jail broken. This process should work for you just fine if you follow the directions in the link I listed.
 

Skyhigh223

macrumors regular
Jul 21, 2009
151
0
Just to clarify a couple of the points raised by Skyhigh223,



Correct with the exception of the current 8GB MC model which is a 2nd gen but has the new bootrom which does require signing by Apple when restoring so can not be downgraded unless you have your SHSH blobs backed up for the version firmware you are downgrading to.



Partially correct, however on the original pre 2009 release MB model 2G touch the soft SHSH checks only apply to 4.0 and future releases so for example if you updated to 4.1 you could not go back to 4.0 unless you had your SHSH blobs for 4.0 backed up. You can however still go back to 3.1.3\3.1.2 or earlier.


Cheers :D

Sorry for any misinformation, OP. :p
 

zen

macrumors 68000
Original poster
Jun 26, 2003
1,713
472
Okay, nothing works.

My iPod is definitely an MB model (2nd gen, 8GB).

Putting it into DFU mode makes no difference. Trying to restore with either 3.1.2 or 3.1.3 gives the following message:

"The iPod "iPod" could not be restored. The device isn't eligible for the requested build."

So, looks like I'm stuck until Apple release an update/fix/downgrade tool.
 

zen

macrumors 68000
Original poster
Jun 26, 2003
1,713
472
So... have you tried using pwnage tool or redsn0w on your device?

redsn0w doesn't recognise the iPod.

Pwnage created a new ipsw file, and then I presume I need to restore from that so the iPod is jailbroken.

But then what? How do I restore the jailbroken 4.0 to 3.1.3? Do I follow the same steps as above and it will somehow skip the verify bit? Or is there some jailbreak tool to deliberately install 3.1.3 on it without all that?
 

TBi

macrumors 68030
Jul 26, 2005
2,583
6
Ireland
pwnagetool lets you install the new IPSW directly from it (well it did for me once before).

BTW you create a jailbroken 3.1.3 file... not a 4.0 file. You should be able to downgrade to that.

Others have done this. Why don't you google it and see what it comes up with.
 

zen

macrumors 68000
Original poster
Jun 26, 2003
1,713
472
pwnagetool lets you install the new IPSW directly from it (well it did for me once before).

BTW you create a jailbroken 3.1.3 file... not a 4.0 file. You should be able to downgrade to that.

Others have done this. Why don't you google it and see what it comes up with.

pwnage won't let me create a jailbroken 3.1.3 file. It will take the 4.0 ipsw (the version currently installed on the iPod) and creates a jailbroken version of that. If I browse for an ipsw and select either the 3.1.3 or 3.1.2 file, I get an error in a big red box saying "wrong firmware bundle selected".
 

TBi

macrumors 68030
Jul 26, 2005
2,583
6
Ireland
pwnage won't let me create a jailbroken 3.1.3 file. It will take the 4.0 ipsw (the version currently installed on the iPod) and creates a jailbroken version of that. If I browse for an ipsw and select either the 3.1.3 or 3.1.2 file, I get an error in a big red box saying "wrong firmware bundle selected".

Get an older version of pwnage tool. Find out what version was used for 3.1.3 and use that.

Might be worth going back to 3.1.2 as i remember you had to use that for some unlocks.
 

Aeroplane

macrumors member
Aug 29, 2008
44
0
this is all sorts of crazy.

i want to get some apps but i need 4.2, ugh, im gonna hav to learn to backup my shsh thingie aaaack.

so how are 2nd gen ipods on 4.2 ? much lagging? anynone care to reply? jaja
 

baryon

macrumors 68040
Oct 3, 2009
3,875
2,922
I can't believe there's no easy way to downgrade. I mean, why can't we simply format the storage of the iPod and clone an image of an iOS 3 installation onto it, as you would do with a computer? An iPod Touch is just a smaller computer.

Also, why doesn't Apple test their software before releasing it? If they would have tested it, they would have seen that it runs far too slow to be useable. It turns a perfectly fine 2Gen Touch into a slow piece of ****.

I hate how they're implying "you're too stupid to make decisions" and also "you've owned this iPod for more than 6 months, it's time to buy a new one to keep doing what you've done before without problems".

I think they should just put a timer in every device they make, and after 6 months it would pop up with a nagging message every 10 minutes, saying "pay us more money and buy a new device again!". I'm sure it would work better.
 

TacticalDesire

macrumors 68020
Mar 19, 2012
2,286
23
Michigan
When I was using iOS4 on my 2g I didn't notice many performance issues at all. It was barely noticeable going from iOS 3 to 4. At least for me.
 

Menneisyys2

macrumors 603
Jun 7, 2011
5,997
1,101
When I was using iOS4 on my 2g I didn't notice many performance issues at all. It was barely noticeable going from iOS 3 to 4. At least for me.

Yup, Apple forgot to artificially slow down the iPod touch running 4.2.1, unlike with the iPhone 3G. That phone they did slow down - almost the same hardware and, still, orders of magnitude slower than the iPod touch 2G running on 4.2.1. Even without a SIM card.

----------

so how are 2nd gen ipods on 4.2 ? much lagging? anynone care to reply? jaja

Perfectly usable, I say. Except for Apple's making it almost impossible to release apps that do support it. Less than two years (mid Sep/2012) after they stopped (late Sep/2010) selling it.
 
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