Oh! No new posts since a few days. I was thinking on what I should make a new post. Then I thought, lets make a post on downgrading iOS. There are many articles, tutorials on how to downgrade iPhone Operating Systems all over the internet, but here's mine.
A few days ago, I did a downgrade from iOS 4.0.1 to 3.1.3. In a past post, I described how to 'Upgrade' from iOS 3.1.3 to 4.0.1. Now in this post, I will show how to 'Downgrade' iPhone firmware (Operating System) from 4.0.1 to 3.1.3.
What Is Upgrading and Downgrading?
In simple words, In an Upgrade (Updating iPhone Operating System), you goes advance to your current firmware. For example, if you are on iOS 3.1.2 and you update it to 4.0 then its Upgrade.
Downgrading is the opposite process of Upgrading. In a Downgrade, you comes back to a previous iPhone firmware version. For example, if you are on iOS 4.0.1 and you comeback to iOS 3.1.2, its downgrade.
OK let's start the Downgrading process.
Things needed for Downgrading.
- Saved SHSH blobs (Refer to this post on why and how to save SHSH blobs)
- The firmware you need to downgrade to.
- A latest version of iTunes.
- RecBoot. (To get out of recovery mode. Download link are at the end)
- A Little Patience and,
- A cup of coffee. (No download links ;-p)
Software/Materials used in this tutorial.
- iPhone 3GS on iOS 4.0.1
- iTunes 10.0.0.68
- iOS Firmware version 3.1.3
- RecBoot v1.3
- Operating System - Windows 7.
- Coffee - Strong, with less sugar.
Downgrading from iOS 4.0.1 to 3.1.3
First thing you need to do is to keep things ready mentioned above. After everything is ready, follow the steps.
First, you need to change to host file on your PC. To do this, go to - C:\Windows\System32\drivers\etc\ and open the file - hosts with Notepad. Add the following line at the end of the file.
74.208.105.171 gs.apple.comNow the hosts file will look like this. (Click on any image to enlarge it.)
Now save the file.
Connect you Device to PC.
Now you need to put your iPhone in Recovery Mode. To do that, press and hold the Home button and Power button at the same time and hold for atlest 10 seconds. After that, release the Power button, but keep holding the Home button. Windows will install Apple USB Driver. Your Device should now show the connect to iTunes logo and iTunes will show message that it has detected iPhone in Recovery Mode. You can release the Home button now. Your Device is in Recovery Mode.
Click OK
Now that your device is in Recovery Mode, we will Restore it to the version we want. To do so, press and hold SHIFT key on keyboard and click on Restore button in iTunes. Browse to the firmware file and select it. Click Open. iTunes will show a confirmation message that this process will erase and restore device to the selected Operating System version.
Click Restore.
iTunes will now verify the restore with Apple. We have changed the hosts file earlier so no problem with that.
Now its time where you will need patience and a cup of coffee. Sit back and let the process finish. Until then, keep patience and have coffee.
Keep an eye on the bar displayed in iTunes and your device's screen. When the process will finish, iTunes will show an error message. It can be error 1015, 1013 or 1011 saying restore was not successful because of an unknown error. Don't worry. This is normal and we are done with the Restore.
Now we need to get out of the Recovery Mode. We'll have to use RecBoot for this.
Run RecBoot.exe and click "Exit Recovery Mode" and your Device will be out of Recovery Mode and it will boot normally.
When the iDevice will reboot, iTunes will detect it and ask you to setup a new iPhone or restore from a backup. You'll need to setup a new device as the files stored on your device when it was in iOS 4.0.1 were new and they will not work for iOS 3.1.3. But you can use a backup if you were on same major iOS version. Like Downgrading from iOS 3.1.3 to 3.1.2.
Click continue and iTunes will do rest of it.
So what now? Well you've just Downgraded your iDevice! Game is over. Now you do what ever you want with it. Jailbreak it, Unlock it, install new apps, add some videos, pictures whatever. Because you are now able to use it with the Downgraded iOS.
These steps can be followed to downgrade to any version from any version. There's no difference (as long as it comply with the condition of having SHSH blobs)
Download Links
Download iTunes
Download RecBoot (For Windows, Mac, and Linux)
Useful Links
How to Backup SHSH Blobs
Upgrading iOS
Note : Please be aware that you can Downgrade to only the iOS version, SHSH Blobs of which you have saved. If you did Jailbreak before, and used Cydia, then SHSH Blobs for your device are saved automatically. For example, if you were on iOS 4.0 when you Jailbroke and saved SHSH blobs, you can not downgrade to iOS 3.1.3 but 4.0.
If you have no SHSH blobs saved, you can NOT downgrade.
Caution : You will loose ALL data on your Device in this process.
Warning : Do this process at your own risk.
Advice : If you need any help, feel free to ask.
