Downgrading to ISO 4.0

[Eric Noa]

I have a Jailbroken and unlock iPhone 4 running 4.1 and I want to downgrade so that I can activate FaceTime with MiTime, then I will upgrade to 4.1 again and jailbreak and unlock. What is the best method to downgrade to 4.0?

 

[PsstGreek]

I have a Jailbroken and unlock iPhone 4 running 4.1 and I want to downgrade so that I can activate FaceTime with MiTime, then I will upgrade to 4.1 again and jailbreak and unlock. What is the best method to downgrade to 4.0?

If you have the SHSH files saved for 4.0 then you can downgrade. Only way.

 

[Eric Noa]

If you have the SHSH files saved for 4.0 then you can downgrade. Only way.

I have them all...

 

[PsstGreek]

I have them all...

Then you're good to go. All you need to do is this: http://www.iclarified.com/entry/index.php?enid=7556 (Mac)

http://www.iclarified.com/entry/index.php?enid=7557 (Windows)

 

[Eric Noa]

Thank you... I will give it a try later

 

[PsstGreek]

Thank you... I will give it a try later

No problem

 

[Eric Noa]

Then you're good to go. All you need to do is this: http://www.iclarified.com/entry/index.php?enid=7556 (Mac)

http://www.iclarified.com/entry/index.php?enid=7557 (Windows)

Im going to try this now but will it work? It says its for the iPhone 3GS

 

[Eric Noa]

Didn't work. It gives me an error (21)

 

[labman]

couple things it might bea bad usb port try another or a bad cable connector. or you might need to try another version of Itunes and make sure you are running tiny umbrella here is a good tutorial. error 21 is also possibly a hardware issue.

http://www.redmondpie.com/downgrade-ios-4.1-to-ios-4-3.1.3-3.1.2-how-to-guide/

 

[PsstGreek]

Error 21 is a hardware like said above. If you restore again it will work, just put your iPhone back into DFU mode. Eventually the error will come back again when you need to restore at another time.