Downgrade Apple iOS 4.2.1 to 4.0.1/4.0.2/4.1 firmware

Recently Apple has released the latest i OS 4.2, but the biggest disadvantage of the latest firmware is it is still not yet jail breaked. Not only this but also a new boot ROM is found in all new i OS devices which doesn’t allow the ultra-snow to unlock the device either which makes this i OS un jail breakable and can’t be unlocked either. But since many of them might have upgraded out of curiosity and might have found all these problems. Surely, you can’t afford to buy a new one just because of reason but yes you can’t live just like that too, so we will guide you in this process where in you can down grade back to 4.0.1 or 4.0.2 or to even 4.1 for your i Phone 3G, 3GS and also i Phone 4 and Apple iPad too.  You can also downgrade Apple iPhone 3 GS to 3.1.3 from iOS 4 or even you can downgrade your i Phone firmware from 2.2.1 to 2.2. Before proceeding to the procedure to downgrade, you will need to download the appropriate firm wares which are listed below:

Downloads:

• iOS 4.0.1: iPhone 3G, iPhone 3GS, iPhone 4

• iOS 4.0.2: iPhone 3G, iPhone 3GS, iPhone 4

• iOS 4.1: iPhone 3G, iPhone 3GS, iPhone 4

Procedure to downgrade:

• Firstly, you need to download the required firmware for the downgrade from the available download links given above.
• Then you need to put your device in DFU mode and not in Recovery mode. You can easily put your i Phone into DFU Mode.
• Please note, the users of iPhone 3GS, iPhone 4 and i Pod touch 2G (MC model) users who have their SHSH blobs (ECID SHSH) saved on Cydia for the firmware downgrading, If you don’t have your SHSH files saved, you cannot downgrade to any of the i Devices mentioned above in the list. Please note that the users with non-MC model do not need to follow this step and can skip to the next step.
• Now, you will need to navigate to the system folder, C:WindowsSystem32driversetc and look for a file which is termed as called hosts.
  
• The users who are on Mac OS X can browse this file by going to /etc/ and then find from “Go to finder”, after this you will have to open this file on any text editor like notepad (for windows) and Text edit (for Mac OS X) and add the following the code at the end of the file as 74.208.105.171 gs.apple.com.
  
• Now after adding at the end, just Save and click on Exit from File.
• After adding that in the notepad, Now you are now ready to restore your i Device with the firmware which you have opted to download from the above mentioned list. Now allocate your device from the side bar of iTunes and press and hold Shift on Windows and left alt on Mac OS X then click on Restore tab. Now just release the pressed button and you need to navigate to the iPSW folder and select your downloaded firmware and then press OK to proceed.
  
• Now, it is time to relax after so much of work until iTunes does the rest for you by itself. Please do not open or do anything as i Tunes will downgrade to your required firmware. It might be possible that after certain updates i Tunes will give an error saying This i Device could not be restored. An unknown error occurred (1004 or 3194), don’t panic and ignore the message as the firmware has already installed on the device successfully.
• You will find that your device is still in recovery mode by showing you a of “Connect to iTunes” on the screen. To fix this download, you will have to install a program called “Tiny Umbrella” for (Windows / Mac OS X). Now just run this program and click on “Kick device out of recovery” button. You should now see your device restarting in normal mode.

Now, you will find that your device is now running successfully the downloaded firmware which you wanted to downgrade your i Device to. You can also fix i Phone restore mode loop after downgrade.