Myth behind Downgrading iOS 4.0.2 to iOS 4.0.1 without SHSH Blobs

Well, it sounds very exciting when we here that it is possible to downgrade from iOS 4.0.2 to iOS 4.0.1 or iOS 4.0 without SHSH Blobs. So, in previous tutorials (Mac / Win), I have mentioned that there is a possibility of downgrading your iOS 4.0.2 running devices to iOS 4.0.1 to iOS 4.0. Well, trying that method will not hurt because, anyway you are stuck with iOS 4.0.2 for now. If it works, you can go ahead and Jailbreak it. If not you can get to your previous state (iOS 4.0.2).

Semaphone, the man behind Tiny Umbrella/Firmware Umbrella shared his thought on Downgrading iOS 4.0.2 to iOS 4.0.1 / iOS 4.0 without SHSH Blob. Well, according to him it is not at all possible.. This is what he says..

Let me get this out first.

1. This is not a miracle, at least not in the sense you all hope for
2. SHSHs are STILL required for any iPhone 4, iPhone 3GS, iPad, iPod Touch 3G, and iPod Touch 2G (MC Model)
3. There is NO way around this… unfortunately this method included.

Let me start by explaining something very important. The buildmanifest is used by iTunes to build much of the TSS request that is used to obtain your SHSH for any given firmware revision. Unfortunately, the BuildNumber has no part to play in the request for SHSH. All that you ended up doing in following these directions is request 4.0.1 SHSH blobs. THAT IS ALL. Since every single one of you that got this to work changed your hosts file to point to Cydia, Cydia responded to the TSS request with an SHSH blob that was ALREADY “on-file”. There was no magic. There was no miracle, apart from the lucky break that your device had been put on Cydia’s SHSH request list at some time in the distant past.

That’s it in a nutshell folks. There was no amazing technique for bypassing Apple’s TSS. There was no amazing exploit that exists in DFU mode allowing for 4.0.2 -> 4.0.1 downgrading. It’s simple; Cydia had your SHSH because at sometime in the past either:

• Someone saved your SHSH with that device using TinyUmbrella and the default options
• Someone restored that device with Cydia in the hosts pointing to gs.apple.com
• Someone jailbroke the device and pressed ‘Make my life easier’

How To Downgrade Your iPhone From iOS 4.0.2 to iOS 4.0.1/iOS4 Without SHSH Blobs [Windows]

This is really an awesome news for those who have upgraded to iOS 4.0.2 and want to downgrade it back to iOS 4.0.1 to take advantage of JailbreakMe (as the iPhone Dev Team is not planning to release a jailbreak tool for iOS 4.0.2). Until now, it is only possible if you have saved SHSH Blobs for iOS 4.0.1. But, it looks like there is a possibility of downgrading from iOS 4.0.2 to iOS 4.0.1 or iOS 4.0 with out SHSH Blob. With that said, lets not waste any more times and get started. Let us know if this work around worked for your.

Read the Myth behind Downgrading iOS 4.0.2 to iOS 4.0.1 without SHSH Blobs

Warning: Please do it on your own risk. We will not be responsible for any damage or breakage of your iPhone.

Step 1:

Download iPhone Firmware Version (iOS 4.0.2 & iOS 4.0.1/ iOS 4.0)

Step 2:

Now, extract the ipsw file that you have just changed using WinRaR

Step 3:

Open the Buildmanifest.plist with Notepad.

Step 4:

Now, Click “Control” + “F” to get the Find Windows

Step 5:

Here, Find and replace all “8A306″ (if you are using iOS 4.0.1)/ “8A293″ (if you are using iOS 4.0) with “8A400″.

Step 6:

Now, Open the Restore.plist with Notepad

Step 7:

Now, Click “Control” + “F” to get the Find & Replace Windows.

Step 8:

Here, Find and replace all “8A306″ (if you are using iOS 4.0.1)/ “8A293″ (if you are using iOS 4.0) with “8A400″.

Step 9:

Now, take the iOS 4.0.2 firmware file, rename its extension from .ipsw to .zip

Step 10:

Extract the iOS 4.0.2 file that we have just rename its extension and leave it open.

Step 11:

Now, move all the iOS 4.0.1 / iOS 4.0 files to iOS 4.0.2 windows (Folder that we have open in Step 11)

Step 12:

Once moved, Delete all the dmg files that have 002 at the end, leaving only the 001 files left and Close this windows.

Step 13:

Now, Change the iOS 4.0.2 firmware extension to .ipsw from .zip

Step 14:

Navigate to the following folder “C:\Windows\System32\drivers\etc”

Step 15:

Now, look for the file name hosts and open it with Notepad

Step 16:

Add the following line at the bottom of the file (if you have 127.0.0.1 gs.apple.com in the file comment it out by adding # in front of the line)

74.208.10.249 gs.apple.com

Step 17:

Now, click on File and select Save

Note: To double check if you updated the hosts file – Open one more terminal window and type “ping gs.apple.com” you should get some thing like this ..

• PINGING gs.apple.com [74.208.10.249]: 32 data bytes of data:
  

Step 18:

Now, grab your iPhone, plug it in and lets put your iPhone into DFU mode.

• Here, iTunes will alert your that “iTunes has detected an iPhone in recovery mode. You must restore it before it can be used.” Click okay

Step 19:

Now, it time for us to restore the firmware – Hold down the “SHIFT” key and click on “Restore“.

Step 20:

That’s it! Now, you can just sit and relax and let the restore finish.

How To Downgrade Your iPhone From iOS 4.0.2 To iOS 4.0.1/iOS 4 Without SHSH Blobs [Mac]

This is really an awesome news for those who have upgraded to iOS 4.0.2 and want to downgrade it back to iOS 4.0.1 to take advantage of JailbreakMe (as the iPhone Dev Team is not planning to release a jailbreak tool for iOS 4.0.2). Until now, it is only possible if you have saved SHSH Blobs for iOS 4.0.1. But, it looks like there is a possibility of downgrading from iOS 4.0.2 to iOS 4.0.1 or iOS 4.0. With that said, lets not waste any more times and get started. Let us know if this work around worked for your.

Read the Myth behind Downgrading iOS 4.0.2 to iOS 4.0.1 without SHSH Blobs

Warning: Please do it on your own risk. We will not be responsible for any damage or breakage of your iPhone.

Step 1:

Download iPhone Firmware Version (iOS 4.0.2 & iOS 4.0.1/ iOS 4.0)

Step 2:

Rename the downloaded file extension from .ipsw to .zip

Step 3:

Now, extract the .zip file that you have just changed.

Step 4:

Open the Buildmanifest.plist with TextEdit

Step 5:

Now, Click “Command” + “F” to get the Find & Replace Windows.

Step 6:

Here, In the pop up window Type “8A306″ (if you are using iOS 4.0.1)/ “8A293″ (if you are using iOS 4.0) in Find Field & “8A400″ in Replace field

Step 7:

Click on “Replace All” and Save the File

Step 8:

Now, Open the Restore.plist with Text Edit

Step 9:

Now, Click “Command” + “F” to get the Find & Replace Windows.

Step 10:

Here, In the pop up windows Type “8A306″ (if you are using iOS 4.0.1)/ “8A293″ (if you are using iOS 4.0) in Find Field & “8A400″ in Replace field

Step 11:

Click on “Replace All” and Save the File

Step 12:

Now, take the iOS 4.0.2 firmware file, rename its extension from .ipsw to .zip

Step 13:

Extract the iOS 4.0.2 file that we have just rename its extension and leave it open.

Step 14:

Now, move all the iOS 4.0.1 / iOS 4.0 files to iOS 4.0.2 windows (Folder that we have open in Step 13)

Step 15:

Once moved, Delete all the dmg files that have 002 at the end, leaving only the 001 files left and Close this windows.

Step 16:

Now, Change the iOS 4.0.2 firmware extension to .ipsw from .zip

Step 17:

Click on Finder and while holding SHIFT + COMMAND Key press “G”.

Step 18:

In the field type /etc/ and Hit enter.

Step 19:

Now, look for the file name hosts and open it with TextEdit.app

Step 20:

Now, add the following line at the bottom of the file (if you have 127.0.0.1 gs.apple.com in the file comment it out by adding # in front of the line)

74.208.10.249 gs.apple.com

Step 21:

Now, click on File and select Save As and save it on the desktop. (Make sure you un-check “if no extension is provided” and remove the txt. The file should not have any ext.)

Step 22:

Go back to the desktop and drag the hosts file into the etc folder. You need to authenticate it, enterpassword and click on replace to replace with the updated one.

Note: To double check if you updated the hosts file – Open one more terminal Windows and type “ping gs.apple.com” you should get some thing like this ..

PING gs.apple.com (74.208.10.249): 56 data bytes

Step 23:

Now, grab your iPhone, plug it in and lets put your iPhone into DFU Mode.

• Here, iTunes will alert your that “iTunes has detected an iPhone in recovery mode. You must restore it before it can be used.” Click okay

Step 24:

Now, it time for us to restore the firmware – Hold down the “Option” key and click on “Restore“.

Step 25:

Select the Firmware and click Open to start the restore.

Step 26:

That’s it! Now, you can just sit and relax and let the restore finish.