This post will show you how to downgrade from iOS 4.3.5 or iOS 5 to any iOS version that you have your SHSH Blobs backed up for. It is important you have your SHSH blobs on file for the iOS version you want to downgrade to. If you donâ€™t have your SHSH blobs on file for the iOS you want to downgrade to, you will not be able to downgrade. You can check which SHSH blobs on file youâ€™ve got by launching Cydia and looking at the top of the Cydia homepage where it lists all your saved SHSH blobs.
1. Run iReb, select your iDevice and follow the on screen instructions to put your device in DFU mode. The steps are as follows:
I. Hold down the power button for 3 seconds
II. Continue holding the power button and start holding the home button and continue HOLDING BOTH for 10 seconds
III. Let go of power and continue holding home button for 20 seconds (or until Redsn0w starts the jailbreaking process).
2. After it is finished, close iReb and run TinyUmbrella.
6. Wait from iTunes to finish restoring your iDevice.
7. After iTunes is finished, you should be on the firmware you selected.
If you did the steps above CORRECTLY and it didn’t work try replacing your hosts file with this one.
1. Backup your hosts file by saving it somewhere you can find it when you are finished.
2. Now drag and drop the hosts file that you downloaded from the link that I provided into the hosts file folder. On Mac OS X it should be located â€œ/etc/hostsâ€ and on Windows it is located â€œC:\windows\system32\drivers\etc\hostsâ€.
3. Now repeat steps 1-7 again and it should work this time. If it doesn’t try another computer.
4. When you are finished be sure to put back your hosts file.
If you use iReb once and get an error. You have to use iReb again because that error will throw your iDevice out of a pwned DFU state. ie if you use iReb and after you get error 3194 then you fix error 3194. You have to then use iReb again because you iDevice is no longer in a pwned DFU state. Or you will get error 1013 or a 1600 error.