Downgrade Your iPhone 4 Firmware From 4.0.2 to 4.0.1
Okay so you got your iPhone 4 on firmware 4.0.1 or 4.0 and all of a sudden you have a major crash (probably due to “trials”, tweaks you have been installing or using Rock app). Now Cydia doesn’t want to open, your apps are crashing. Yup you have to restore now! The only problem is, Apple is only allowing you to restore to iOS 4.0.2 which is does not have a jailbreak. What Now!!?
This is how to bypass Apples signature server so you can restore to firmware 4.0.1 or 4.0 and re jailbreak your iPhone 4.
NOTE: For this to work, You previously would have had to backed up your SHSH Blobs for 4.0.1 or 4.0 via Cydia or TinyUmbrella. If your iPhone 4 came with iOS firmware 4.0.2, you unfortunately are screwed until a new jailbreak is released.. which probably wont be until firmware 4.1.
Apple decided that every restore of the device would be verified as being valid and safe by Apple itself.
To do this, during the restore process, users see “Verifying restore with Apple…”, during which time a challenge/response protocol is used between the iPhone and Apple: a “partial digest” of the firmware files being used is sent to a server, which can then decide to sign off on the result… or not.
Not only does this allow Apple to keep custom firmwares from getting loaded onto the device, but it also allows them to recall existing firmwares by keeping people from restoring to them in the future.
You will need to edit your hosts file located here – C:WindowsSystem32driversetchosts (Windows) or /etc/hosts (Mac OS X) and add 74.208.10.249 gs.apple.com to the bottom.
Doing this will trick iTunes to think it’s talking to Apple, when in reality it is talking to Cydia instead, therefor bypassing Apples limitations.
This is how to bypass Apples signature server so you can restore to firmware 4.0.1 or 4.0 and re jailbreak your iPhone 4.
NOTE: For this to work, You previously would have had to backed up your SHSH Blobs for 4.0.1 or 4.0 via Cydia or TinyUmbrella. If your iPhone 4 came with iOS firmware 4.0.2, you unfortunately are screwed until a new jailbreak is released.. which probably wont be until firmware 4.1.
Apple decided that every restore of the device would be verified as being valid and safe by Apple itself.
To do this, during the restore process, users see “Verifying restore with Apple…”, during which time a challenge/response protocol is used between the iPhone and Apple: a “partial digest” of the firmware files being used is sent to a server, which can then decide to sign off on the result… or not.
Not only does this allow Apple to keep custom firmwares from getting loaded onto the device, but it also allows them to recall existing firmwares by keeping people from restoring to them in the future.
You will need to edit your hosts file located here – C:WindowsSystem32driversetchosts (Windows) or /etc/hosts (Mac OS X) and add 74.208.10.249 gs.apple.com to the bottom.
Doing this will trick iTunes to think it’s talking to Apple, when in reality it is talking to Cydia instead, therefor bypassing Apples limitations.