i have done the forbidden 1.2.0 upgrade by accident too.
i have followed the big boss guide and still "No Signal"
(I am running iTunes 7.6 on a mac)
This is what I have tried so far:- DFU mode and restored to 1.1.4 two time to be sure (got the 1015 error)
- ran independence 1.4 to get out of recovery mode
- ran kZiphone and downgraded the basedband (reported successful)
- ran pwnage. it pwned the phone no probs, then created the IPSW file, when i restored in iTunes using the custom ipsw file i get a 1604 error back.
So i DFU restored again to 1.1.4 using the original iphone firmware file
- then ran iLiberty. This reported successful also
- but still the "no service"
- so i ran iClarified baseband downgrader in installer
- said it was done
- restored to 1.1.4 in itunes
- unlocked with iLiberty (tried entire thing again with Ziphone)
- still no signal
so i went through the whole process again
- this time i tried boot neuter
- it too reported successful
- restore in itunes
- no signal
what am i doing wrong
is it itunes. should i be running 7.5
if so what do i need to go from 7.6 to 7.5 on a mac
i know there are a million and one people asking about downgrading back to 1.1.4 but any help on this would be great
cheers