Downgrade iPhone 3GS 3.1 to iPhone 3GS 3.0

With the new iPhone 3.1 update, iPhone 3GS users can no longer downgrade from iPhone 3GS 3.1 firmware to iPhone 3GS 3.0. Apple wants users to stay with the most current firmware. There is no way to jailbreak iPhone 3GS 3.1. No custom firmwares are able to be added on iPhone 3GS either. Fortunately, Saurik, the creator of the Cydia application has come up with a solution. It only works for the few that were able to use Cydia’s “on file” system and “hash” their ECID (ECID is the unique chip ID that each iPhone 3GS device has). If you were one of the few, read on below to find out how to downgrade iPhone 3GS 3.1 to iPhone 3GS 3.0. If you were not one of the few, then you are still lucky. iPhone 3.1 can still be jailbroken, but you’ll need to wait until a full jailbreak solution is out. I’ll post the guide here once it’s out.
How to Downgrade iPhone 3GS 3.1 to iPhone 3GS 3.0
If you are on Windows Vista or Windows 7 you will need to run Notepad as Administrator and then locate the hosts file and edit it. Then move on to step 4.
1. Press Windows + R on your keyboard or go to Run.

2. Type in the following: C:\Windows\System32\drivers\etc\hosts.

3. Click OK. You should now get an Open With window. Click on Notepad and then click OK.

4. Your hosts file will now open in Notepad. Make a new line below 127.0.0.1 localhost and copy and paste in the following:
74.208.105.171 gs.apple.com
5. Click File – > Save in Notepad. Where it says “Save as type” make sure you select All Files and then click Save.
6. Download iPhone 3GS 3.0 (iPhone2,1_3.0_7A341_Restore.ipsw) and save it to your desktop. If you haven’t already, download iTunes 9 and install it.
7. You must now put your iPhone 3GS in Recovery mode. Connect your iPhone 3GS to your PC. Hold down the top iPhone 3GS button and the bottom home button for 10 seconds, let go of the top button but continue holding the bottom home button until iTunes displays the following message: “iTunes has detected an iPhone in recovery mode. You must restore this iPhone 3GS before it can be used with iTunes.” Your iPhone 3GS screen should be black.
8. Open iTunes, press shift on your keyboard and click “Restore“. Locate the iPhone 3GS firmware 3.0 file you downloaded in step 6 and iTunes should now begin restoring it.
Troubleshooting
- If you get unknown error (3002), it means your Cydia on file system was not hashed. You cannot ever downgrade to firmware 3.0. Just stay on iPhone 3GS 3.1 firmware for now and wait for the iPhone 3.1 jailbreak to be released.





122 Comments
wah. i cant find (iPhone2,1_3.0_7A341_Restore.ipsw) file.
does anyone here able to save it? can you re up it pls?
thank you.
This does not work!!! I used the proper ipsw and my iphone does have an ECID on file with Cydia. However, I don’t know what changing the the host file has to do with any of this. If it is supposed to trick the phone to get the ECID from Cydia…it didn’t. I changed the hostfile as per the instructions. In case I did something wrong please let me know.
“I don’t know what changing the the host file has to do with any of this”
Don’t post, if you don’t know! The entry in the host file is to preventing iTunes from connecting to gs.apple.com and redirecting it to the IP 74.208.105.171. This is just the trick to get a allowance from iTunes to install “not eligible” firmware.
Must this work only in iTunes 9
If it is, will Purplera1n be able to work on this?
Seriously, when will the Jailbreak for iPhone3GS 3.1 come?
I didn’t try it yet, even, I’m scared :(, I guess, that I have done the backup, but, I’m not sure what backup it was, just, I found Cydia suggested that it will be better so, I agreed :):) I’m still new to IPhone esp. the 3Gs version, but, I want to clarify something, the hosts file is important for redirecting requests, I mean, when you write http://www.google.com so, this domain name (google.com) must be translated into an IP address, and the system (windows/mac) do check this file first before querying the DNS server, and the IP address which is provided in the Article is just an IP address of Cydia domain name :), so, whenever ITunes want to authenticate your restore file, it connects to Cydia instead of Apple.com :), and Cyida will handle the response with your file.
That’s all, I hope it’s clear, and I hope I could have the carriage to do it and I’ll let you know.
All the best for every IPhoner :)
To let you all know that, it didn’t work for me, the Cydia backup was corrupted :(, it’s very unpleased, and I guess, the Iphone will be used as a racket till we find a jailbreak for the 3.1 :)
Regards,
Ok i downgrade and i succesfully jailbreak using Redsnow. But for some reason i dont have any service or any signal. What is the solution? I hAve tried to do the process so many times but still no good.
Did you find any solution as yet for your phone?
I have a similar problem. The phone is everything else but a phone.
If you get help, please let me know.
mistakenly updated my 3GS to 3.1, just after a week of use. Now ive been exposed to the world of the Jailbreakers, freezers, brickers, Chosen ones!! What do i do? Get another phone or wait for the downgrade… Will it ever come? someone tell me it will come. Im desperate. Its an amazing phone!!
That is so unfortunate that I am the few who bought an iPhone 3GS (White 32GB) still unbreakable. I would like to pay for the sofware but I also want to test them before purchase. Please let me know if there is any solution to JailBreak the Ver. 3.1.Thanks in advance.
When is the new jailbreak coming out for OS 3.1? Its been over a week now and its driving me crazy not having my iphone jailbroke. Give us some answers or at least some updates on when this will happen.
there is a 3.1 jailbreak with pwnage tool for people who did not update with itunes
e hi, i have a problem with downgrade 3.1.2 to 3.0 iphone 3gs i think i try everything i could all ways i get a same error (Thiphone could not be restored This device isn’t eligible for the requested build) now i need help please thanks ..
Me too. Not eligible. Any ideas?
My 3GS died (ya, OK…FINE! So I screwed with it until I bricked it…you happy?) It was at 3.0.1, and it DID in fact have the SHSH files at Cydia. Unfortunately it was toast in such a way that the only way I was able to revive it was an official “Restore” – which of course made it 3.1. I have found several variations of the above instructions online. From what I have learned (through about 20 failures and 1 success) is the following:
Use this value in the HOSTS file: 74.208.105.171 gs.apple.com – some videos and instructions mistakenly give you this: 74.208.105.172 gs.apple.com
Use DFU mode – NOT recovery mode. If you see the happy cable coming up from the bottom of your screen to plug into iTunes logo then NO, YOU ARE NOT IN THE RIGHT MODE. In DFU mode the screen is completely black. If you don’t know the difference might I suggest a new tool known as Google?
OK, the HOSTS file thing is confusing to many people (based on comments on like 50 sites). I understand not everyone is an I.T. geek, so I will explain this. iTunes verifies that your phone can be restored with the version you are trying to use by contacting a particular server at Apple (named “gs” in this case). When iTunes goes out to get approval it looks up the IP (that is the actual address) of the server, gs.apple.com (gs is the hostname, apple.com is the domain). All workstations will look at their local HOSTS and on Windows LMHOSTS files first – then go to DNS servers next. By adding this one line you are basically tricking your machine to go to the Cydia server instead of the GS server to check for the certificates/permission to perform the upgrade. There seems to be a lot of people with security concerns here – which begs the obvious question, “Why the hell are you jailbraking your phone with untrusted software in the first place?” If you trust enough to Jailbrake and put many, many piece of software from people all over the world (even some 12 year old in Russia) then changing one host value on your system is the absolute LEAST of your worries.
Make sure you are using iTunes 9 and the restore file: iPhone2,1_3.0_7A341_Restore.ipsw – I tried others and they did not work. If you Google this file name you get hundred of hits as to where to download it so there is no need for me to post that here.
OK…this is absolutely CRITICAL. In order for this to work AT ALL you had to have had an iPhone at 3.0.x, jailbroken, connected to Cydia and allowed it to copy your SHSH stuff. Jay only had this process up for a VERY short window. It has long since been shut down and if you didn’t do it at 3.0.x then it is pointless anyhow. You would know if your information is stored – you would have had to have allowed Cydia to extract it and every time you went to Cydia you would see a message that says This iPhone has an SHSH file at Cydia or something like that on the top of the screen. It you are not sure, then there is a 99.9% chance you did not have it and you just need to live with 3.1.x….deal.
Another thing that is mentioned in some of the tutorials – you WILL get an error (though there is some discrepancy as to which error) the first time you do this. After it fails, do it again. You will get an error again at the Restoring iPhone Firmware part after the recovery, but this time you have been downgraded. As per several tutorials and my experience it works the second time…sort of
After this your iPhone should be in a loop and only boot to Recovery Mode (cable/iTunes logo). There are two ways out of this – one, use iRecovery (again, Google is your friend) to get out of this, or just Jailbrake at this point – either works.
For far more information go here:
http://www.saurik.com/id/12
And remember to thank Jay every chance you get.
This did not work for me either – I have tried it on 3 different PC’s, although all running the newest itunes 9.0.1.8, could it be that apple is not using some thing other than gs.apple.com?
Hello friends, i have a problem with 3.1.2 iphone 3gs i think i try everything i could all ways i get a same error (The iphone could not be restored This device isn’t eligible for the requested build) now i need help please thanks, I tried many time to get ON my device but is is in recovery mood, I am stuck to working my phone in original position.
I can not save the hosts-file after paste in the “74.208.105.171 gs.apple.com”. i get a message when i trying to save that says contact admin to save or something. I have one user on my pc, and then i have to be admin, but i can still not save the file, do you know what im going to do?
Ok, i have SHSHs save on Cydia from 3.1 to 4.0.1.
I had a jailbroken/unlocked iPhone 3GS running 3.0.1 but decided to give 3.1.2 a try. Turnes out the 3.1.2 blows more than having a iPad and running a fake iPhone app on it to fool your friends of having a REAL iPhone!!!
Anywho, I tried ALL ways that i found on google and guess what, none of them tell you what to do when you get an error from iTunes that says “Your iPhone is not eligible for the requested build”
Can anyone post a solution/resolution to this problem?