Restore iDevices to older firmware


Recommended Posts

Apple, in all of their infinite wisdom, have decided to make it hard to downgrade iOS versions. This makes things awkward when you need to use an older version for jailbreaking or any other reasons that I can't think of. It is possible to downgrade by having SHSH blobs on Saurik's server, but you probably don't and that's why you're reading this guide. This method works by editing some of the files in the .ipsw file that contains the firmware to trick Apple's verification system into thinking that you are restoring to the current firmware.

7zip can be found here:

http://www.7-zip.org/

iPodRobot plist Editor is somewhere over here:

http://download.cnet.com/Plist-Editor/3000-18551_4-10909598.html

You can find .ipsw files here:

http://www.felixbruns.de/iPod/firmware/

Note: This has only been tested on an iPod Touch 2G because that is all I have. This does not work for 3.1.3 (for me anyway). Your mileage may vary.

Other Note:I did not think of this, I found it after updating to 4.1, not liking it and googling for a way to fix it.

Even more notes: Click the images to enlarge.

1. Download the ipsw file you will be restoring to an put it somewhere on your computer.

141280221t.png

2. Make all file extensions visible.

202664515t.png

Press the Alt key and select Tools>Folder Options...

243690625t.png

Got to the View tab and uncheck Hide extensions for known file types. Apply and close.

3.Make a new folder and copy the .ipsw into it so you have two copies with the same filename.

4. Rename the file to a .zip.

373219498t.png

Rename it changing only the extension to .zip.

324642055t.png

Because you are changing the file type you will get a warning, click Yes.

5. Open the .zip and copy the BuildManifest.plist and Restore.plist files into the folder with your .ipsw file.

717631988t.png

6. open the .plist files with iPodRobot.

714393633t.png

Find and replace the original build number with the build number of the latest firmware for your device. It should appear twice or three times in BuildManifest.plist and once in Restore.plist.

The build number is in the file name and next to the device name on the list here.

The file name should be in this format:

ipod2,1_4.0_8A293_Restore.ipsw
"device name"_"version number"_"build number"_Restore.ipsw

7. Create the modified firmware.

702630091t.png

Delete the BuildManifest.plist and Restore.plist files from the .zip file and copy in your modified .plist files in their place. Rename the zip file into an .ipsw file like in step 4.

8. Finishing.

If you prefer to hide extensions repeat step 2, checking the box.

Open iTunes and connect your iDevice shift click the Restore button and select your modified firmware. From here, continue the restore as normal.

If you get a 1394 error, you are using the wrong build number, try older build numbers, 8B117 seems to work on iPod Touch 2G (as of January 2011).

T8

Link to comment
https://www.neowin.net/forum/topic/972006-restore-idevices-to-older-firmware/
Share on other sites

I tried using the method but I keep getting a 3194 error.

I have 4.2.1 on a 4G iTouch and I'm trying to get down to 4.1. I have edited the firmware, but it doesn't seem to be tricking the apple servers.

Do I have to edit the file name to match the new firmware as well?

I guess it's no luck for 4G 4.2.1ers as of now?

I tried using the method but I keep getting a 3194 error.

I have 4.2.1 on a 4G iTouch and I'm trying to get down to 4.1. I have edited the firmware, but it doesn't seem to be tricking the apple servers.

Do I have to edit the file name to match the new firmware as well?

I guess it's no luck for 4G 4.2.1ers as of now?

3194 is the one I meant at the end of the first post. I think it means the build number you used is for an older firmware which they don't want you using anymore or its for a different device.

The latest build number for your iPod (4G) is 8C148. The example I used was for a 2G.

T8

3194 is the one I meant at the end of the first post. I think it means the build number you used is for an older firmware which they don't want you using anymore or its for a different device.

The latest build number for your iPod (4G) is 8C148. The example I used was for a 2G.

T8

I used 8C148.

It gave me 3194.

I've even tried doing it with tinyumbrella in a separate tutorial. No success.

I tried using the method but I keep getting a 3194 error.

I have 4.2.1 on a 4G iTouch and I'm trying to get down to 4.1. I have edited the firmware, but it doesn't seem to be tricking the apple servers.

Do I have to edit the file name to match the new firmware as well?

I guess it's no luck for 4G 4.2.1ers as of now?

Try TinyUmbrella, it'll "kill" the process to connecting to Apple Servers.

The build number for 4.1 worked for me but it probably won't work for restoring to 4.1. I don't know what else to suggest. Tiny umbrella won't work by itself because you need apple to verify the restore, iTunes needs to receive the "OK" message from apple or it will give you the 3194 error.

T8

I tried using the method but I keep getting a 3194 error.

I have 4.2.1 on a 4G iTouch and I'm trying to get down to 4.1. I have edited the firmware, but it doesn't seem to be tricking the apple servers.

Do I have to edit the file name to match the new firmware as well?

I guess it's no luck for 4G 4.2.1ers as of now?

Just thought, did you edit the restore.plist file too, I didn't include a picture for that one and didn't make it that clear.

I had a go at doing it for your ipod, will link to the file when it uploads so you can test it, these retina graphics make it a huge file :/

T8

it seems that if you buy an ipod 4g that already has 4.2.1 on it there is no way to downgrade it to 4.1,

not really sure what they changed but it can not be done

if you've upgraded to 4.2.1 you can downgrade back to 4.1 but not if the ipod's only had 4.2.1 for whatever reason

Just thought, did you edit the restore.plist file too, I didn't include a picture for that one and didn't make it that clear.

I had a go at doing it for your ipod, will link to the file when it uploads so you can test it, these retina graphics make it a huge file :/

T8

can you send me a link too, i'm trying to get my friends new ipod downgraded so he can jailbreak it, if it doesn't work i guess we'll just have to wait till greenpois0n's 4.2.1 jailbreak is released :/

I tried using the method but I keep getting a 3194 error.

I have 4.2.1 on a 4G iTouch and I'm trying to get down to 4.1. I have edited the firmware, but it doesn't seem to be tricking the apple servers.

Do I have to edit the file name to match the new firmware as well?

I guess it's no luck for 4G 4.2.1ers as of now?

The whole ipsw isn't going anywhere on my connection :no: but here are the files you will need to move into the ipsw replacing the existing copies.

BuildManifest.plist

Restore.plist

iPod touch 4g restoring down to 4.1 ONLY

T8

The whole ipsw isn't going anywhere on my connection :no: but here are the files you will need to move into the ipsw replacing the existing copies.

BuildManifest.plist

Restore.plist

iPod touch 4g restoring down to 4.1 ONLY

T8

you put the same link for both files

Got some good news for you, Greenpois0n has been released for iOS 4.2.1

http://lifehacker.com/5752219/greenpois0n-brings-a-long+awaited-untethered-jailbreak-to-ios-421

Tried to look in the .dmg files in the .ipsw but they're encrypted :(

T8

awesome, just in time to give the ipod back to my friend tomorrow

that was the whole reason for trying to downgrade it was so i could jailbreak it

crap, just realized it's only released for osx right now :/

if i'm lucky i'll be able to log onto one of the macs at school tomorrow and do it from there

This topic is now closed to further replies.
  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Posts

    • As I've been usually saying lately - we all can thank "AI" for this.
    • Friday Windows 11 preview builds are here. Insiders in the Experimental (formerly Dev) and Beta Channel can download builds 26300.8697 and 26220.8690. My Windows11 device on the Preview Channel just got 26220.8728. My guess is this build is a nightly update from 26220.8690.
    • Traffic has a surprisingly unexpected impact on your surroundings by Sayan Sen Image by Radik 2707 via Pexels A collaborative study by researchers from several Israeli institutions found that everyday pollution from traffic and industrial activity measurably changed the atmospheric electric field over the Tel Aviv metropolitan area, providing new evidence of how human activity can influence the lower atmosphere. The research was led by Dr. Roy Yaniv of the Hebrew University of Jerusalem and the Gertner Institute at Sheba Medical Center, Dr. Assaf Hochman of the Fredy & Nadine Herrmann Institute of Earth Sciences at the Hebrew University, and Prof. Yoav Yair of Reichman University. The study also involved Itay Froomer, a student from Hadera High School and the Israeli Museum of Medicine and Science (Technoda), who carried out the work as part of the Ministry of Education's 5-unit physics research track. The researchers focused on the atmospheric electric field under fair-weather conditions. Even in the absence of storms, a weak electric field naturally exists between Earth's surface and the atmosphere. One of the main ways scientists measure this field is through the Potential Gradient (PG), which is the inverse of the vertical component of the electric field. PG is a key part of the global electric circuit, a planet-wide system of electrical currents maintained by thunderstorms and electrified clouds around the world. Scientists have long known that the atmospheric electric field can be influenced by factors ranging from large-scale atmospheric processes to local weather conditions such as dust, fog and clouds. Human-made pollution is also known to play a role, but understanding exactly how urban emissions affect the electric field close to the ground has remained an area of ongoing research. To investigate this relationship, the team analyzed measurements from a newly installed electric field mill, an instrument used to continuously monitor the strength of the atmospheric electric field. The instrument was installed at the Center for Technological Education (Roter House) in Holon and became operational in August 2024. It was funded by Israel's Ministry of Education and the Holon municipality. The electric field mill forms part of a broader monitoring network that includes nearby meteorological stations and air-quality monitoring sites. This allowed researchers to compare electric field measurements with detailed weather data and pollution records to better understand what was driving changes in the Potential Gradient. The study focused on two major urban pollutants: fine particulate matter (PM2.5) and nitrogen oxides (NOx), both commonly produced by vehicle traffic and industrial activity. PM2.5 refers to microscopic airborne particles small enough to remain suspended in the atmosphere for extended periods, while NOx is a group of gases released during fuel combustion. Researchers examined daily, weekly and seasonal patterns in the atmospheric electric field and compared them with changes in pollutant concentrations. Their analysis revealed a clear relationship between NOx levels and changes in the Potential Gradient, particularly during morning and evening rush hours when traffic emissions were at their highest. “What we observe is a direct physical link between emission peaks and electrical variability,” explained Dr. Roy Yaniv. “NOx reduces atmospheric conductivity very quickly, so the electric field responds almost instantaneously during traffic rush hours.” Atmospheric conductivity describes how easily electrical charges move through the air. According to the researchers, nitrogen oxides rapidly alter this conductivity, causing a near-immediate response in the electric field. PM2.5, however, was associated with a delayed response. The researchers attributed this difference to the particles' longer atmospheric residence time, meaning they remain in the atmosphere for longer periods, as well as their different microphysical interactions with surrounding air and atmospheric components. The study also identified a pronounced "weekend effect." In Israel, traffic volumes and some industrial activity decline significantly on Fridays and Saturdays. During these periods, concentrations of both NOx and PM2.5 dropped, and corresponding changes were observed in the atmospheric electric field. “The weekend signal demonstrates just how sensitive the electric field is to changes in human activity,” the researchers noted. “When emissions decline, the electrical environment adjusts at once, providing a high-resolution indicator of urban atmospheric conditions.” The findings showed that pollution levels can influence not only the chemical composition of the atmosphere but also its electrical properties. Researchers said the results strengthened the case for using atmospheric electricity as an additional tool for environmental monitoring, particularly in densely populated urban areas where anthropogenic, or human-caused, influences are most pronounced. The study also pointed to potential public health applications. By combining air-quality measurements with observations of atmospheric electricity, researchers said they could gain a more complete picture of how urban atmospheric conditions change over time. “Integrating air-quality data with electric-field measurements gives us a clearer picture of how the lower atmosphere evolves moment by moment,” the researchers added. “It’s a framework that can support both scientific insight and practical environmental decision-making.” Beyond the scientific findings, the project highlighted a collaboration between universities, public institutions and secondary education. Researchers said the work demonstrated how students could take part in real-world environmental research while contributing to studies of air quality, atmospheric processes and their potential effects on society. Source: Hebrew University, ScienceDirect This article was generated with some help from AI and reviewed by an editor. Under Section 107 of the Copyright Act 1976, this material is used for the purpose of news reporting. Fair use is a use permitted by copyright statute that might otherwise be infringing
    • We aren't even at the all-star game and Microsoft is talking about an update that will most likely be released during the World Series if not after. A lot can happen in the world between now and the 2026 World Series, including the 2026 FIFA Cup. Tell me about it again after the FIFA Cup is concluded. That should allow plenty of time to prepare for it.
    • Great, tell me when I have a "Bad Pool Caller" elsewhere not in Windoze.
  • Recent Achievements

    • Week One Done
      AMV earned a badge
      Week One Done
    • One Month Later
      AMV earned a badge
      One Month Later
    • Collaborator
      ryansurfer98 went up a rank
      Collaborator
    • One Month Later
      Eurosoft10 earned a badge
      One Month Later
    • Week One Done
      Eurosoft10 earned a badge
      Week One Done
  • Popular Contributors

    1. 1
      +primortal
      542
    2. 2
      +Edouard
      186
    3. 3
      Michael Scrip
      77
    4. 4
      PsYcHoKiLLa
      77
    5. 5
      Steven P.
      71
  • Tell a friend

    Love Neowin? Tell a friend!