iPhone Restore iOS 8 using old iTunes backup, possible?

[Cubytus]

Hi to all,

like many others, I learned the hard way iOS 9.2 isn't compatible with iTunes 11.4 on Snow Leopard.

First a quick background: I bought a used iPhone 5c from a friend who never upgraded it past iOS 8.3. He was just fed up with Apple screwing the updates, and asked for an official unlock from his carrier.

I used it for a few days, but for some reason, it refused to connect to my calendars nor sync to iTunes, saying it wasn't configured, except it was. Since there was no irreplaceable data on it, I wanted to do a full reset, and used the Settings menu to do that. Except, it didn't go as expected, and the phone stood stuck on the Apple logo while happily draining the battery. Then Genius Bar. Phone restored using their own "floaters". Now iOS 9.2.1. Other problems now: calendars synchronize properly, but movie tickets I had in Passbook aren't transfered to Wallet, IMAP-based notes I have been keeping on the two Macs, previous iPhone and iPad aren't displayed; toggle is activated, but nada: notes counter desperately show 0. I didn't even have the chance to perform an OTA upgrade to 9.2.1, which is said to be the correct way of keeping Snow Leopard sync-ability.

Except that iOS 9.2.1 can't sync with iTunes 11.4. It needs 12, which in turns requires OS X 10.8 at least.

After reading this topic on a French forum, I come here for some advice: if my friend has a proper Time Machine backup from mid-2015 and if he backed up the iPhone to his computer, if he ever performed the upgrade using iTunes, would it be possible to restore, first iTunes media folder, then one of his phone backups, along with iOS 8.3? Would such a backup contain the signed .ipsw unique to this iPhone?

 

[C DM]

The signing gets checked at the time of install not something that gets saved or anything like that.

 

[Paddle1]

Hi to all,

like many others, I learned the hard way iOS 9.2 isn't compatible with iTunes 11.4 on Snow Leopard.

First a quick background: I bought a used iPhone 5c from a friend who never upgraded it past iOS 8.3. He was just fed up with Apple screwing the updates, and asked for an official unlock from his carrier.

I used it for a few days, but for some reason, it refused to connect to my calendars nor sync to iTunes, saying it wasn't configured, except it was. Since there was no irreplaceable data on it, I wanted to do a full reset, and used the Settings menu to do that. Except, it didn't go as expected, and the phone stood stuck on the Apple logo while happily draining the battery. Then Genius Bar. Phone restored using their own "floaters". Now iOS 9.2.1. Other problems now: calendars synchronize properly, but movie tickets I had in Passbook aren't transfered to Wallet, IMAP-based notes I have been keeping on the two Macs, previous iPhone and iPad aren't displayed; toggle is activated, but nada: notes counter desperately show 0. I didn't even have the chance to perform an OTA upgrade to 9.2.1, which is said to be the correct way of keeping Snow Leopard sync-ability.

Except that iOS 9.2.1 can't sync with iTunes 11.4. It needs 12, which in turns requires OS X 10.8 at least.

After reading this topic on a French forum, I come here for some advice: if my friend has a proper Time Machine backup from mid-2015 and if he backed up the iPhone to his computer, if he ever performed the upgrade using iTunes, would it be possible to restore, first iTunes media folder, then one of his phone backups, along with iOS 8.3? Would such a backup contain the signed .ipsw unique to this iPhone?

You can't downgrade because Apple isn't signing iOS 8. The only way to get iOS 8 would be to jailbreak and go through a slightly tricky process which isn't possible right now because there's no jailbreak for the current version of iOS.

Unless you can upgrade your Mac from OS X 10.6, to get the phone to work with iTunes you'll need to use a different computer.

 

[Cubytus]

Actually I had the time to perform a jailbreak on iOS 8, but I also read that the saved SHSH blob was now useless…

 

[iLG]

No

 

[iOSUser7]

Actually I had the time to perform a jailbreak on iOS 8, but I also read that the saved SHSH blob was now useless…

Not exactly, they were useless for some time but are useful again since the release of the latest TinyUmbrella.

As of today, you can downgrade any 32 bits device (including the iPhone 5) to any iOS version you want with the Odysseus downgrade tool as long as you have saved the SHSH blobs and bundles are made for your device model (for example iPhone5,1).

However, last time I checked back in June, there was still some baseband issues after the downgrade but it could have been fixed now.

I'm not sure about the iPhone 5C but you may have a chance (if you saved SHSH) because it share the same internals as the iPhone 5.
Also, I don't know if you need to be jailbroken first (which is impossible on iOS 9.2.1) in order to downgrade to an older version.

 

[stooovie]

Basically, it's impossible, sorry. The OS doesn't restore from backup - it downloads from Apple and needs to be signed. The only thing in iOS backup is the data, not the OS.