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It’s finally here folks, the official downgrade tool for A5 devices!
Starting with redsn0w version 0.9.11b1, those with newer devices (iPad2, iPad3, and iPhone4S) can join the downgrade fun too!
In a radical departure from previous versions of redsn0w, it now directly supports restoring IPSWs to your device. The first use of this new feature implements a hack that allows A5 downgrades without a bootrom-level exploit.
Indeed, you can now downgrade your iPhone 4S, iPad 2, or new iPad (iPad 3) with the latest version of RedSn0w 0.9.11b1. Downgrading will allow you to perform an untethered jailbreak on your iPhone 4S, or iPad 2 running iOS 5.0.1 firmware.
Check out our tutorial for the step-by-step downgrade instructions inside…
Note: You must have your SHSH blobs for iOS 5.0.1 either stored locally by means of TinyUmbrella, etc., or Cydia must have your 5.0.1 blobs for this downgrade to work successfully.
Step 1: Download the latest version of RedSn0w 0.9.11b1 RedSn0w 0.9.11 beta 1: Mac • Windows
Step 2: Download the latest firmware (5.1.1) for your device from our downloads page, along with the 5.0.1 firmware.
Step 3: Place your device into DFU mode.
Step 4: Run RedSn0w 0.9.11b1, and make sure RedSn0w detects your device in DFU mode. Navigate to Extras > Even more > Restore and click IPSW under the IPSW section. RedSn0w will then ask you for your iOS 5.0.1 IPSW. Once you locate iOS 5.0.1, RedSn0w will ask your for the latest firmware (iOS 5.1.1).Step 5: Once both firmwares have been validated, it’s time to locate your saved SHSH blobs. If you’ve jailbroken your device before, you should have those available on Cydia, and therefore you can use the Remote option. If you’ve never jailbroken your device before, but you saved your SHSH blobs with a tool like TinyUmbrella, then choose Local and browse your computer for your blobs. We’d recommend clicking the Remote option first.Step 6: Once your blobs have been verified, there is nothing left for you to do, just let RedSn0w execute the full process. First RedSn0w will install a hacked version of the latest firmware (iOS 5.1.1), and then it will downgrade your firmware to iOS 5.0.1.
Step 7: Upon downgrading successfully you will be presented with a success message. Now all you have to do is setup your device, and verify that you are now on iOS 5.0.1 via Settings > General > About on your device.What’s Next?
Most people will want to jailbreak their newly downgraded device. If you’re using an A5 device like the iPad 2, or iPhone 4S, you can now jailbreak using Corona-A5. You can do this directly from RedSn0w. We will have a tutorial that shows you how to jailbreak your A5 device using RedSn0w in the near future. Until then, you can always use a tool like Absinthe Absinthe v0.4: Mac - Windows - Linux to jailbreak as well.
Were you able to downgrade successfully? Have any tips or tricks? Please share them below!
Important: If you rely on a software unlock or SIM interposer for your iPhone, beware! This method will update your baseband, and you could permanently lose your unlock.
UPDATE
5x redux
What’s old is new again!
Jailbreakers with devices that pre-date the iPad2 will always be able to downgrade (with SHSH blobs) to previous firmware versions due to geohot’s limera1n exploit, which allows us to bypass the restrictions that Apple places on restores. But until now, that ability has been limited to those older devices (if you have an older device and don’t know how to do that, check the popular tutorial sites or ask in the comments below).
Starting with redsn0w version 0.9.11b1, those with newer devices (iPad2, iPad3, and iPhone4S) can join the downgrade fun too! In a radical departure from previous versions of redsn0w, it now directly supports restoring IPSWs to your device. The first use of this new feature implements a hack that allows A5 downgrades without a bootrom-level exploit.
Some important points:
- The new feature is at Extras->Even More->Restore
- You cannot downgrade without the personalized SHSH blobs for your device at that lower firmware. You need to have fetched those blobs while the signing window was open, using either Cydia’s built-in TSS@Home feature, or with TinyUmbrella. The new Restore screen of redsn0w lets you choose either the remote blobs or local ones (for the earlier firmware). If you don’t know where TinyUmbrella put your blobs, TinyUmbrella has a button that will show you (copy them out of that folder and feed them to redsn0w).
- The A5 downgrade method actually updates to the latest firmware before downgrading to the earlier one. This process updates your baseband to whatever is newest. DO NOT USE THIS METHOD IF YOU RELY ON UNOFFICIAL UNLOCKS of your iPhone4S. Those who used the temporary SAM technique to unlock their iPhones to specific SIMs shouldn’t be affected by this baseband update.
- This method can be fixed by Apple with a firmware update. It’s a (pleasant) mystery why they haven’t fixed it yet, because reverse-engineering of the restore ramdisk indicates they do know about it. It’s possibly too niche to bother to fix right now.
- The least-tested devices with this method are the iPad2,3 and iPad3,2 (because we don’t have those models). If you do and you feel like experimenting, please let us know how it turns out in the comment section below!
- This update involves a bunch of new redsn0w code. We recommend sticking to the previous version 0.9.10b8b unless you’re specifically using this new feature, until all the bugs are worked out! (Note: If redsn0w gets stuck at the “Waiting for device” stage for more than 30 seconds, you’ve hit a pesky GUI bug…that will be fixed in an upcoming version!)
Of course all eyes are on @pod2g for his upcoming 5.1 untethered jailbreak. Watch his blog or twitter feed for the latest updates about that, but in the meantime if you accidentally updated your jailbroken A5 device to something later than 5.0.1, feel free to try this new A5 firmware downgrade feature of redsn0w!
Update #1: We accidentally left out one of the two flavors (“9A406”) of 5.0.1 for iPhone4S. It’ll be in the next update, but in the meantime check if Cydia or TU saved your blobs for the other 5.0.1 for iPhone4S (“9A405”). Version 0.9.11b2 adds support for that second “9A406” flavor of 5.0.1 for the iPhone4S.
Update #2: Version 0.9.11b3 should fix the spurious “Restore failed” messages people were sometimes getting, and it behaves better with nearby devices that have wifi syncing enabled!
Update #3: Version 0.9.11b4 completes the tethered JB support for 5.1.1 on A4 devices and earlier, including proper “Stitching” and “Custom” creation of NO_BB IPSWs.
Here are the redns0w download links:
- redsn0w 0.9.11b4 for OS X
- redsn0w 0.9.11b4 for Windows (be sure to run in Administrator mode)