How To Downgrade iOS 4.3 To iOS 4.2.1 [Full Guide]

Today and with this Guide, I will show you to how to  downgrade its iOS 4.3 to 4.2.1 with an IOS requirements and error 1013 in iTunes 10.2.1

Currently it is possible to downgrade its iOS 4.3 to a previous iOS if you do not meet certain conditions:

First you must to have your file SHSH signed prior to an iOS

 Again I remind you that your baseband version changes with each update the IOS and return is not possible to have an older version baseband even restoring an old IOS.

 Baseband current version only allows to restore an IOS version that corresponds to baseband (for the latest version of baseband).

 Although you changed the host file or use TinyUmbrella TSS with its server, you get an error of type 1013 following the restoration of the IOS with 4.2.1 to 4.2.1 SHSH signed

 1-Launch the iTunes software, restore iOS 4.2.1 with the ALT key (Shift for Windows) + click on "Restore" in iTunes.

2-Restoring runs but will crash at 3 / 4.
 

3-Wait for the error 1013 via iTunes.

4- Close iTune

5- Now your in Mode recovery "Cable iTune"

6-Press the button (above) and Home (down) until the expiry of your iDevice.

7-Then immediately go into DFU mode , press the ON button 3 seconds and then ON + HOME for 10 seconds, then HOME button just 17 ​​seconds.

8- Launch the software jailbreak Greenpois0n .

9-Follow the steps in the guide after switching to jailbreak DFU mode.

10-Your iDevice then jailbroken 4.2.1 under iOS then connect to iTunes to finish its activation following the restoration of previously iOS 4.2.1.

   

Note: You must have the original SIM card to activate your iPhone after restoring the IOS.


[Via iPhonex] 

For more news coverage, you can follow us on Twitter or become a fan on our Facebook page, we will keep you updated with posts over the web.