Apple has released iOS 4.0.2 to fix the PDF exploit used by JailbreakMe 2.0 star, the ultimate jailbreak for all devices on iOS 4/ iOS 4.0.1 or iPad 3.2.1. Those of you who have upgraded to iOS 4.0.2 accidentally or had bought a new device which came with it, check our articles on how to jailbreak iOS 4.0.2 on iPhone 3G using Redsn0w 0.9.5b5-5 and jailbreak iOS 4.0.2 on iPhone 3GS using PwnageTool (unofficial).
If you are an iPhone 4 user, then you are left with no way to jailbreak and unlock iOS 4.0.2. Your only choice at this time is to downgrade iOS 4.0.2 to iOS 4.0.1 using your saved SHSH blobs. In case you are one of those who forgot to save your SHSH blobs or lost them, then here is some news for you. A guy by the name UndeadRevolution has posted a guide on PwnMyI Forum on how to downgrade iOS 4.0.2 to 4.0.1 without having your SHSH blobs saved.
Disclaimer: We have not tested this method, and also have no confirmation so far of it’s success. Proceed at your own discretion. We are not responsible in case of any damage to your device.
Those Who Saved SHSH Blobs on Cydia, jump to this article on how to downgrade iOS 4.0.2 to iOS 4.0.1, 4 on iPhone 4, 3GS, 3G and iPod Touch 3G, 2G.
Here are the steps to downgrade iOS 4.0.2 to iOS 4.0.1 without SHSH blobs
1. Download iOS 4.0.1 IPSW and iOS 4.0.2 IPSW files (links at bottom).
2. Rename the file as .zip and then extract it’s contents using WinRAR to your desktop.
3. Open buildmanifest.plist and restore.plist files using a text editor.
4. Search and replace the string 8A306 with 8A400 through out the documents. Save both the files.
5. Now open iOS 4.0.2 IPSW file using WinRAR or WinZip. You should be able to double click and open it if you have either of the utilities installed. Do not extract it’s contents, simply open it.
6. Copy all files from iOS 4.0.1 folder and drag and drop them into iOS 4.0.2 file opened in WinRAR.
7. Delete all .dmg files with 002 at the end. This leaves only those dmg files with 001.
8. Save the iOS 4.0.2 file in WinRAR and change back it’s file extension to IPSW.
9. Open the hosts file on your Computer and add this line at the end.
74.208.10.249 gs.apple.com
Refer to our article on how to block websites using hosts file if you are having trouble finding it on your PC.
9. Open the hosts file on your Computer and add this line at the end.
74.208.10.249 gs.apple.com
Refer to our article on how to block websites using hosts file if you are having trouble finding it on your PC.
9. Put your iPhone into DFU mode.
Plug in your iPhone to your Computer and turn the device off. With iTunes running, hold down the Power and Home buttons for around 10 seconds. First release the Power button, still holding the Home button. Wait till your Computer shows up a new USB device.
Now open iTunes and let it restore your iPhone to the modified firmware.
That’s it. You should now be able to go ahead and jailbreak and then unlock your iPhone.
Have you tried this method and is it working? Let us know in the comments.
