TUAW How To: Downgrading your 3.1.3 iPhone to 3.1.2

Last week I downloaded (but did not install) the iPhone OS 3.1.3 firmware for my 3GS. I wanted to have a copy of the firmware on hand, but didn't want to upgrade right away. I checked "Do not ask me again" and clicked Download Only. I thought that was the end of the matter.

Unfortunately, this Sunday, I plugged in my iPhone and left the room to grab some tea. When I returned, the iPhone was 50% of the way through the 3.1.3 firmware upgrade procedure. It did something I had no idea that it would do: it upgraded me without asking.

How frustrating! What's more, I didn't have a copy of 3.1.2 on-hand to downgrade to because iTunes automatically deleted the old firmware files and I was using default Time Machine settings; Time Machine does not normally back up ~/Library, the folder that contains the iTunes ipsw files.

Fortunately, I had several resources. First, because I had jailbroken my phone and registered my device signature with Jay Freeman's caching service, I knew I could downgrade my phone. As Jay and I discussed in this LiveChat from a few months back, Apple no longer allows you to freely downgrade your iPhone software. All firmware installations must be verified with Apple's signature servers.

By jailbreaking your phone and registering your device signature with Jay's system, you'll be able to bypass Apple's verification system and return to the firmware you prefer -- or at least to the earliest firmware whose signature you have stored on the caching site. To make this happen, you must both register your device and update your /etc/hosts file. Jay's site has complete instructions on how to comply.

Second, I could grab a copy of old firmware from sites like Felix Bruns' http://www.felixbruns.de/iPod/firmware/ and iClarified's http://www.iclarified.com/entry/index.php?enid=750. These sites provide Apple download links for old firmware releases. I downloaded a fresh copy of the 3.1.2 ipsw (iPhone software archive) and installed it onto my system. Using a standard option-restore trick, I was able to put that firmware onto my iPhone. iTunes verified the upgrade with Jay's server and installed it onto the device.

Note: If you receive the "The iPhone could not be restored. An unknown error occurred (3004)." error, make sure to quit iTunes and flush caches at the command line: sudo dscacheutil -flushcache.

If your device updates properly, you will receive a 1015 error and your unit will now enter a semi-permanent recovery mode, the mode in which your device shows an iTunes logo and will not boot further. To proceed, you'll need to use iRecovery. Download a copy from this site. (It requires libusb, so read the entire post before running.) Run iRecovery from the command line and supply the -s flag. Wait for the "]" prompt, and do not type anything until you see that prompt appear.

Enter the following commands:

] setenv auto-boot true

] saveenv

] /exit

After, you will return to the command line. Reboot your phone by pressing the home and sleep buttons for 10 seconds, per the instructions on the site, and your iPhone should boot back to standard 3.1.2.

Note: Be aware that this method does not downgrade your baseband. It remains at the 3.1.3 setting.

Thanks Jay Freeman, Sjoerd (aka WiFone), and Paul "PhoenixDev" Griffin

Source: http://tuaw.com/tag/hacks

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Last week I downloaded (but did not install) the iPhone OS 3.1.3 firmware for my 3GS. I wanted to have a copy of the firmware on hand, but...

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Bilboy

check out this tutorial on how to downgrade your iphone 3g or 3gs at iphonerepo.webs.com

May 04 2010 at 1:24 PM Report abuse Permalink rate up rate down Reply

ceejay

to those users of iphone 3gs that has the 3.1.3 firmware you can now jailbreak it by using SPIRIT :)

check this out! it works! http://is.gd/bT1bb

May 03 2010 at 10:50 PM Report abuse Permalink rate up rate down Reply

seaweede

okay so i went to felixbruns like everyone told me to to update my ipod touch firmware to 3.2.1. 1/2 way through the download i get an error mssg and computer starts going crazy. not responding, stuck on some stupid any spyware window. I rebooted in safe mode and kapow! Stuck with some "copywrite/piracy" warning. Can't do a damn thing on my computer now. No vista, no internet access (cannot connect). Thanks felix. Thanks for the virus. Thanks for what it's gonna cost for fixing the damn thing. I hope to God i don't lose everything. Here I come, Geek Squad.

April 29 2010 at 9:23 PM Report abuse Permalink rate up rate down Reply

synthezise

Device: iPhone 3G running 3.0.1 Jailbroken and Unlocked.. Followed instructions from TII (Today in iPhone)'

Problem: Cydia fails to load, work run.. Can not delete or add any new apps via Cydia..

Want to re-Jailbreak and unlock using 3.0.1 OR would like to update to 3.1.2 and then Jailbreak and Unlock..

I realize I'd have to install all my favorite apps again (Pro Switcher, Backgrounder, City Lights, ect)

"If it ain't broken don't fix it"

It IS unlocked and I AM using the SIM of my choice ...

Cydia apps that had been installed prior to the problem still work..

QUESTION 1: Can I re-jailbreak in 3.0.1?

Yes?

Then what IPSW file do I use?
iPhone1,2_3.0.1_7A400_Restore.ipsw?

Does that sound right?

QUESTION 2: Should I use PWNAGE TOOL?

THANK YOU ALL

April 21 2010 at 4:29 AM Report abuse Permalink rate up rate down Reply

synthezise

Ladies, Gentlemen,
I hate to ask... I need a Jailbreak/UNLOCKING guru.. is there someone on this site who can just answer a few questions?

TIA,
Synth

April 21 2010 at 3:47 AM Report abuse Permalink rate up rate down Reply

Waleed

I upgraded ma iphone to firmware 3.1.3. After reading this article I tried to downgrade it to firmware 3.1.2. So I followed the steps as explained above and I really had my iphone downgraded to 3.1.2 with having the latest modem version 5.12.01. But the new problem is that iTunes cannot recognise my iphone and I can't syncronise ita nymore.
Did somebody have the same problem? Is there any way out of this strange situation?
Thanks

April 19 2010 at 10:29 AM Report abuse Permalink rate up rate down Reply

olbk

Search and visit ur site!
ok, but We're all wondering how the iPhone updated by itself?

-------------
mysite: http://yeucaycanh.com

April 12 2010 at 9:57 PM Report abuse Permalink rate up rate down Reply

william

if this isn't working check out this tutorial

http://iphonerepo.webs.com/apps/forums/topics/show/2334826-downgrading-

April 06 2010 at 10:25 PM Report abuse Permalink rate up rate down Reply

Lqqing2you

I have 3.0 and want to upgrade to 3.1.2, I have an archive version do I "shift restore" will it upgrade to the new firmware? then unlock and jailbreak? I do not want to try the 3.1.3 I would rather wait till DEV team hacks the 3.2 in April. Is there a way to move APPS over or save APPS so I don't have to reinstall them all by hand?

March 17 2010 at 5:24 AM Report abuse Permalink rate up rate down Reply

AgentX69

please help, i have an iphone 3gs with 3.1 firmware i want to know how will I update it to 3.1.2 so i can jail break and unlock it, the problem is there is already 3.1.3....

please help..

thanks in advance...

March 11 2010 at 9:28 AM Report abuse Permalink rate up rate down Reply