Restoring

[SamAun]

Hello all,
I have 4 diff IPhones already synced in my mac. I have with me iphone 3GS 4.2.1.
So, can I restore my 3GS with any of the iphone that are synced in my mac?
And my iphone is jailbreak.

 

[zman2100]

You cannot restore from any phone that's been backed up with a higher version than 4.2.1. So, for instance, if one of the phones is backed up from 5.1 or somthing like that, you wont be able to restore from it unless you update the software first. Additionally, you may have trouble restoring on 4.2.1 since that version is old and Apple is no longer signing it.