How to downgrade or preserve the firmware of your iPhone

[iGaz]

Here's how to downgrade if you've updated your phone and lost your jailbreak. You must of backed up your SHSH's via cydia's make my life easier button for these steps to work. If you are using TinyUmbrella see the links below.

http://www.iphoneforums.net/forum/h...ave-your-shsh-blobs-using-tinyumbrella-18924/

http://www.iphoneforums.net/forum/h...tinyumbrella-check-shsh-you-have-saved-19552/

This guide is based on windows xp but vista and 7 are very similar. You can also follow these steps if you want/need to restore your phone but don't want to be forced to upgrade while doing so. It saves having to downgrade afterwards.

If your blobs for your current firmware aren't saved via cydia or tiny umbrella then you've probably missed the signing window where apple are still allowing you to restore to that firmware normaly. The signing wondow is usually a couple days after a new firmware is released. In this case your only option is to use iFaith. This will pull the blobs from your device from your current firmware only. You can then follow the steps below once you have your required blobs.

Only if you pressed the make my life easier button in cydia can you follow these steps to get your phone back to a jailbreakable firmware. You can also back up your SHSH's via tinyumbrella but there is a different process for that (see the above links). You must have the relevant SHSH's for the firmware you want to downgrade. If you don't have any SHSH's backed up then you can't downgrade unless you have an early bootrom 3GS or any 3G.

So here's how to downgrade on windows XP via cydia.

First download the firmware you want to downgrade to. A list of all firmwares can be found in the link below,

http://www.iphoneforums.net/forum/i...ple-ios-firmware-download-links-iphone-17213/

Remember to choose the correct firmware file for your device. Verzion users need the CDMA files for everyone else it's the GSM. iPhone 4 and 3GS firmwares are also different.

While thats downloading go to,

C:Windows/System32/drivers/etc and open the hosts file with notepad. At the bottom on a new line copy and paste this...

74.208.10.249 gs.apple.com

iTunes must be closed when adding the line. Make sure you press save and then close the window. Some people my also need to reboot thier computer. Once you've done that and the firmware is downloaded get your iPhone into DFU mode. If you don't know how to get you phone into DFU any jailbreaking program (redsnow for example) has a guide that will show you how, or watch this video guide from YouTube.

[ame]http://www.youtube.com/watch?v=bITIiGswjFI[/ame]

If you are still struggling see the guide here,

http://www.iphoneforums.net/forum/iphone-jailbreaking-17/dfu-mode-dummies-16020/

Once in DFU open iTunes. It should detect your phone in DFU and tell you to restore it. Hold shift on your keyboard while clicking on restore and show iTunes the ipsw file you just downloaded from the links. At the end you may get an error 'could not restore iphone' this is normal. Just use tiny umbrella to kick it out of recovery.

If you've clicked the make my life easier button you should be on your new (old) firmware and able to get an untethered jailbreak with redsn0w. If not you will need to restore again in the usual way to the latest version. You may need to delete the line you added in the hosts file to be able to do so.

Anyone downgrading from 4.3.4 or above (except iOS 5) will need to follow additional steps to get out of a recovery loop. Please see f4780y's excellent guide below...

http://www.iphoneforums.net/forum/h...ecovery-loop-following-4-3-4-downgrade-17494/

 

[Gregoris]

very handy for those who rely on jailbreak and the apps it brings.. ty

 

[burrellm]

Help with restoring 4.3 back to 4.2.1. I have been trying this for 2 days. I recall clicking the make my life easier button when i had cydia b4 i updated to 4.3. I have followed the above steps however when i go to itunes and click shift and restore my computer files open but when i click on the iphone 4.2.1 restore.ipsw and it opens to a screen that says no items match your search. So i cant actually get a file that is usable.

 

[iGaz]

Are you using the correct firmware file for your phone? The links in the guide are for the GSM iPhone 4 only. I'll add in the links for the 3GS...

*edit* Links added for 3GS

 

[topgun80]

I don't see a "make my life easier" button in cydia. I upgraded cydia to.7 becuase of another problem, is it not there on this release?

 

[iGaz]

If you have somthing like 4.1 4.2b3 4.2.1 at the very top in green then you've already pressed it...

 

[topgun80]

It says SHSH: iOS 4.2.6 and it's not in green. I don't need to downgrade just wondering just in case

 

[iGaz]

If it's orange then it's still pending. Should go green in a few days max.

 

[topgun80]

It's in gray and it's been that way for quite awhile. It's not a big deal ,just that I've seen that mentioned several times.

 

[iGaz]

Don't know why it's grey. Perhaps something to do with you being on verzion? It won't be a problem unless you upgrade when it becomes availible...

 

[steiner6]

can someone please please help me jailbreak/unlock my iphone 3gs. Its running 4.3.1 and i cant figure out how to get in unlocked so i can use it on t-mobile. Im stuck without a phone i was told the process was easy but i must be just dumb enough to not be able to do it..someone pleaes help me out i am stoked to have an iphone but i need help. I am brand new to iphones and i need someone to literally hold my hand through the process..the phone is brand new and doesnt have cydia on it yet..it doesnt have anything on it yet but 4.3.1 and im not sure what or how to do this.

 

[iGaz]

Only if you pressed the make my life easier button in cydia can you follow these steps to get your phone back to 4.2.1 or 4.1. You can also back up your SHSH's via tinyumbrella but there is a different process for that. You must have the relevant SHSH's for the firmware you want to downgrade. If you don't have any SHSH's backed up then you can't downgrade unless you have an early bootrom 3GS or any 3G.

What this means is if your phone came with 4.3.1 on it or you upgraded to 4.3.1 without saving you SHSH's first then you can't go back. So you will need to wait for the 4.3.1 jailbreak to come out. Then if you wish to unlock, as you have a 3GS, you can upgrade your baseband to the iPad baseband to do so. It does however come with risks, please see the link...

Dev-Team Blog - Ultra-recycle

 

[steiner6]

Thanks for the heads up? Any idea when the 4.3.1 jailbreak will be released? And once that comes out I will ALSO have to update to the ipad baseband in red snow to unlock it via cydia? Sorry if this sounds redundant but im new to this and i really dont want to mess up my phone. Thanks for all your help!

 

[iGaz]

There's never ETA on new jailbreaks. However it shouldn't be too long now.

You can do it either way. Just remember once you update to the iPad baseband there is no way of reversing it like the jailbreak. So you will forever have to restore or update with a custom ipsw with that baseband on it. If you try to update/restore with a stock ipsw from iTunes you will just get an error...

 

[steiner6]

thats fine with me if its not reversable. I update to the ipad baseband through redsnow or whicever i have running right? and once the jailbreak is released thats all i will have to do to get my phone running on t-mobile? Sorry again for all the questions i just want to make sure i do it right the first time so i can use my phone. I am without a phone cuz i was told this process was easy. any other tips or info you think i should have please let me know and thanks again so much for all your help. How do i go about updating with a custom ipsw? im not sure what that means?