How to: Upgrade / jailbreak iPhone 3G with iOS4 and redsn0w

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iPhone 3G JailbreakingPhoto credit: patrick h. lauke (Flickr)

WARNING: If you rely upon a carrier unlock (sim unlock) to be able to use your iPhone 3G please DO NOT follow this guide.  Updating to iOS4 in the detailed manner will upgrade your iPhone’s baseband permanently.  The jailbreak team may release a sim unlock for the new baseband at a later date; however there is also every chance they won’t too!

FURTHER WARNING: Whilst the process we’re going to detail is simple the jailbreak step is recommended only for developers / confident users since the jailbreak method is in a beta state.

LAST WARNING: You can only complete this process if you have either an active sim card for the network that your iPhone should be on, or have a factory unlocked iPhone since the iPhone will need to activate itself via iTunes.

A REMINDER: This process is for the iPhone 3G only.  Separate articles will exist for the 3GS at a later date.

Getting Started

I recommend you read this guide in full, then read it again before you even think about getting started.  I don’t mean to sound condescending; however this is the advice given on even the community pages of the jailbreak team, so it’s worth repeating here.

Whilst the process is proven and widely used, there is almost an element of risk involved.  You undertake the detailed process at your own risk.  Feel free to ask questions in the comments section and we’ll aim to help wherever we can.


Download and install iTunes 9.2

Download iPhone 3G iOS4

UPDATE: Links removed – iOS4 is now available from iTunes; just tell your iPhone to update to the latest version

NOTE: If you decide to jailreak (next section point redsn0w at the downloaded IPSW file.  This can be found in the following location:

On Windows:
Documents and Settings\<User>\Application Data\Apple Computer\iTunes\iPhone Software Updates

On Mac:
~/Library/iTunes/iPhone Software Updates

Upgrade to iOS4

  1. Connect your iPhone to computer and perform a full backup (if necessary, right click your iPhone in iTunes and select backup)
  2. Copy any photos stored on your iPhone to your computer (I accidentally lost mine when updating so it’s best to be safe than sorry!)
  3. Once you’ve verified your backup and ensured you’ve got all your data safe, click on your iPhone in iTunes so the main screen displays options to restore.
  4. Windows users should hold down the shift key and right click the “restore” button.  Mac users should hold down the ctrl and shift keys whilst clicking the “restore” button.
  5. Browse to the IPSW file you downloaded in the pre-requisites section
  6. Once you’ve confirmed your choice you’ll need to sit back and wait about 10 minutes.  Your iPhone will reboot and install the new iOS4 software.
  7. Once the install is successful, iTunes will detect the updated iPhone and ask if you wish to set it up as a new device, or if you’d prefer to restore your settings / data from the backup you made in step 1.  The choice is yours – I personally restored my settings since I didn’t want to have to setup all my email, contacts, wifi access points etc again.

NOTE: After my iPhone had completed its install of iOS4 my iPhone hung on a screen asking to be connected to iTunes and iTunes didn’t automatically pick the iPhone wanted to chat.  The easiest way to overcome such a situation (should it occur for you) is to unplug the iPhone, reboot your computer, open iTunes and reconnect your iPhone.

NOTE 2: If you intend to jailbreak your handset, then I would recommend holding off on spending the time restoring your data until the jailbreak is complete just in case you need to restore and start over again.  It’s unlikely, but I like to be cautious.

Jailbreaking your handset

NOTE: You do not have to jailbreak your handset unless you want to.  If you wish to keep a your iPhone on the vanilla version of iOS4 you can stop now and enjoy the fruits of your labour.  What you’ve installed is what Apple will widely release at a later date via their official channels – you’ve just got it early!  I would just mention that Apple don’t want you to use wallpapers or multi-tasking in the iOS4 release for iPhone 3G.  Even if you jailbreak your handset and do nothing more beyond the initial jailbreak, you can enjoy both of these features on your iPhone 3G!  If you do want to jailbreak then please read on….

It is important to note that at the time of writing this guide the iOS4 update was not widely available.  Many of the applications available on the Cydia/Rock platforms are/were not updated to be able to work on the iOS4 platform and therefore it is imperative that before you attempt to install any jailbreak app that you check it is compatible with iOS4.  Failure to do so and the installation of an incompatible application can result in crashing your iPhone, and in most cases will need a full restore of the iOS platform to recover from.  There’s a spreadsheet detailing compatibility of some apps here.

Jailbreak process

Get the version of redsn0w as appropriate for your computer operating system:

Download Redsn0w 0.9.5 for Windows
Download Redsn0w 0.9.5 for Mac

Extract the contents of the archive to your desktop or other favoured place.

Are you ready?  Let’s begin….

  1. Connect your iPhone to your computer
  2. Close iTunes (if already open or if it opens when iTunes opens)
  3. Power off your iPhone by holding the power button and using the “slide to power off”
  4. Open the redsn0w application and follow the on-screen instructions, typically:
  5. Browse to the IPSW file (details above of where this is located)
  6. Choose whether or not you want wallpaper/multi-tasking enabled on your device (active by default)
  7. Confirm choice and proceed to jailbreak (requires DFU mode)
  8. You have to be on the ball to put your iPhone into DFU mode, it’ll prompt on screen however it’ll involve the following:
  9. Press and hold power button for 5 seconds
  10. Keep your finger on the power button but press and hold the home button too
  11. When prompted (roughly 10 seconds) release the power button but keep the home button pressed
  12. When the device drops into DFU mode redsn0w will change on screen and start to jailbreak the handset.  Hands off the computer and walk away til it’s done (or watch the iPhone)

Once the jailbreak completes your iPhone will reboot.  You aren’t done yet since in this early beta of the jailbreak we need to update Cydia so that you can actually use it.

  1. Open Cydia (a white icon at the moment)
  2. Allow it to refresh itself, after which it will close
  3. Open Cydia again (should be a nice familiar Cydia icon now)
  4. When prompted, install the essential updates only
  5. If necessary, Cydia will close or require a reboot
  6. Open Cydia again, install any remaining updates

You are now in a position to be able to install apps.  Like I said earlier, lots just aren’t ready yet so you should be cautious and check compatibility first.  For example, to install SBSettings, you need to currently add the following repository to your Cydia list:

Personally, that’s all I’ve installed.  There are many others I’d like to install (see my recommended list); however I realise I’ve got to be patient.  At least I can enjoy iOS4 ahead of time and it’s new features safe in the knowledge that as jailbreak apps are updated, I can add them.

Questions and comments

Please ask them in the comments section below.  I’ll endeavour to answer them as clearly as possible.

If you’ve enjoyed or found this article useful, please retweet it, or click the Like button (Facebook users).

Be sure to check back soon for updated guides and info.

Update: 22/06/10

iOS4 got released last night officially.  I’ve therefore removed the links from the article above and suggest you use iTunes to grab the IPSW file.  Furthermore, the previously posted redsn0w links have been replaced with links to a new version since the ones we pointed to worked with the developer GM version of iOS4, they don’t with the version Apple released yesterday.


  • iTunes has said that the restore file is not compatible with my 3g :-/

  • Rob

    Apologies. Have updated the links. Fir some reason they were pointing to iPod restore files!

  • Hehe! I did not even spot that, thank you.

  • Rob

    Silly mistake in my part. Hope you have more luck now!

  • pehpsi

    Does one require an internet connection on the iPhone for Cydia to do its thing?


  • Rob

    You mean like blackra1n did? If so, then no it doesn't.

  • Badilicious


    Thank you for the information.

    I am currently on a Jailbreak 3.1.2 version.. Iphone 3G.. and would like to update to iOS 4 then jailbreak again. However.. Itunes does not allow me to update and refers to problem 3002 (which I have no clue what it is).

    Do I have to :
    1) install to 3.1.3 before upgrading to iOS 4?
    2) Can I install the iOS 4.0 today when apple releases it and use the above jailbreak version? Or does it have to be the iOS 4 beta version?
    3) What else may I do to successfully update?

    Thank you very much for your reply!

  • Rob

    No problem re the post.

    I was on 3.1.2 with a jailbreak before I updated to iOS4. You shouldn't need to unjailbreak, nor should you need to update to 3.1.3 before moving to iOS4.

    Could I just check with you please, you say iTunes won't allow you to update, do you mean you can't update to iTunes 9.2, or you've updated iTunes to the latest version and when you try to apply the iOS4 firmware you get the error?

    On the other points, the linked iOS4 is not a beta but the final release that will be on all iPhone 4 handsets and will be available at a later date via iTunes update.


  • Badilicious

    Wow. Thanks for the quick reply.

    Well I am on Windows 7 and installed yersterday itunes 9.2. When trying to update to iOS 4.0 and error pops-up saying :”The iphone device could not be updated. A unknown problem was detected (3002).

    Then it gives you two options; either OK or more information… and this page provides way to many troubleshoot.. out of which I have tried a few.


  • Badilicious

    Dear Rob,

    I should also advise you since I've downloaded itunes 9.2 – I can't sync my phone. Looked on the net and there are many other users who seem to have the same problem. Any idea ?

    Thanks in advance.

  • Rob

    What jailbreak method did you use to jailbreak your handset currently? I ask, because some of the jailbreak methods will not work with iTunes 9.2

    Re your error message it sounds like one of two things:

    1. The iTunes to iPhone communication drivers haven't installed properly or aren't initiating. Reboot PC (sure you've done this already), or reinstall iTunes 9.2 over the top and then reboot before connecting your iPhone
    2. The iPhone firmware you've downloaded didn't complete properly and therefore iTunes isn't happy with the file. Re-download it and see if it then accepts it as a valid IPSW.

    You do have an iPhone 3G and not an iPhone 3GS don't you? (I know it's a silly question and I apologise for having to ask, but I do have to ask)


  • Badilicious

    Dear Rob,

    Thanks for the reply.

    The phone is a Iphone 3G and I did jailbreak it with blackra1n.

    I will try to reinstall itunes 9.2 and reboot before connecting the phone, but wonder if I can update it through Itunes and yet keep my jailbreak? or do I have to jailbreak it again? Since you mentioned earlier that it isn't necessary to unjailbreak the phone.

    Thanks again for the information.

  • Rob

    If you install iOS4 you will need to rejailbreak using the method I've outlined.

    By installing iOS4 you wipe the firmware completely, erasing any jailbreak installed for older 3.x firmware. I put the section in about not having to remote an existing jailbreak before installing iOS4 because I'm often asked if it's necessary to install a vanilla Apple firmware before then installing a newer OS.

  • Badilicious

    Dear Rob,

    I noticed on Itunes that iOS 4.0 is now available. I've re-installed itunes 9.2 and have rebooted the computer, but still the new version does not allow me to sync. However if I try to restore the phone (maybe it doesnt work)… and it installs the new os 4.0 version… can I follow the above jailbreak version to jailbreak the phone or do I have to wait?


  • Rob

    The jailbreak should work fine provided that Apple hasn't changed anything. Haven't had chance to test myself.

  • Jpkl

    Why cant I just plug in my iphone to a pc and select Install ios4.0 when the itunes pops up asking me to do it or not?

  • Jpkl

    Do i need to reset to default in itunes, before flash to 4.0?
    My version is 3.0.1 (ya..damn old)… modem firmware 04.26.08.. jailbroken.

  • Rob

    You can. Article was updated this pm to reflect that

  • Rob

    No. You can upgrade straight to iOS4 🙂

  • Question… Since I have Cydia Apps that are installed (3.1.3 3G) I believe I want to first install 4.0, do not restore settings and then jailbreak (as mentioned). What I need to know is will it funk my iphone up because some of the apps listed in the spreadsheet are no and some even say crash…

    Also how do you “kick” that in to restore settings?

  • Liam Poole

    umm, i just done this, but i restarted my phone and now ive lost the multitasking, is this normal??? i have everything else tho

  • Liam Poole

    OH, false alarm, it was because i installed winterboard through cydia, and had to restart, i didnt relise it was because of winterboard, silly me, lol…DO NOT INSTALL WINTERBOARD, IT REMOVES MULTITASKING

  • Rob

    When you install iOS4 it will erase the iPhone and the previous jail break so you'll have to install jb apps again.

    Bear in mind that many aren't yet up and running on 4.

  • Dannebeee

    Liam Poole: Do you know if an uninstallation of Winterboard restores multitasking, or do i have to uninstall it and then re-run redsn0w?

  • Rob

    I haven't tried as yet because when I checked yesterday Winterbiard wasn't updated and compatible with iOS4 so I avoided it. You could certainly try and if it doesn't and you are feeling ambitious, you can enable multitasking by editing a plist file (don't have the name to hand but can find it if you are interested.)

    Beyond this it's a restore.

  • Ok so then 1) how do you kick in the “restoring your data” (from Upgrading to iOS4 Note 2) and then 2) So when data is restored it will not restore any cydia apps…

    What about my cracked .ipa files? Should one go install AppSync 4.0 first?

  • any side effects of jail break of ios 4???

  • Rob

    Ahem, prefer not to discuss that on here however in theory the process would be to update, jailbreak, install AppSync then restore your backup.

  • Rob

    There were issues with iBooks but that's now been resolved. If you enable the wallpaper and multi tasking on the 3G there will be a performance hit. Up to you.

  • ok not discussing the .ipa issue… how do you kick in the restore. Is it the “Restore” button that is on the iphone area and choose “restore from backup…”?

    I am cool with having to check and grab cydia apps again as they become 4.0 ready. Just as you said above though all my wifi settings etc. I don't want to lose that.

  • Rob

    You've hit the nail on the head. Right click your iPhone and select the restore from backup option and it'll drop all your apps and settings back on there.

  • Awesome! Thank you!

    Also awesome quick replies 🙂

  • I just did the upgrade via iTunes this morning. There was no option to not restore. Technically I could “see” the option to setup as a new phone but I could not touch it.

    I did not have a choice prior to updating. All the screens simply told me it would backup and restore.

  • Rob

    Very strange. We've done half a dozen phones the last coupla days and all have gone through in the manner we described.

    Thanks for feeding back your experience.

  • Chandasoka

    Hi…I followed ur process, but I cant see my sim network now It's blank and stuck to what I put using MIM.
    Please help.

  • Rob

    Did you rely on a hactivated handset before or is your sim card registered for use with an approved network?

  • I just completed the entire process.

    What I can say is that it takes a long time (at least for me it did).

    I did not have an option to not restore settings. So did that for nothing.
    Then I got errors galore when trying to restore after jailbreaking because I have some cracked .ipa files and so they would not transfer without first updating cydia and grabbing AppSync 4.0.
    After AppSync 4.0 I was able to do a “restore from backup” and after about 2 hours all my apps and settings appear to be back on there.

    One thing I want to mention also is that before I had infiniboard and multi-icon mover which allowed me to rearrange easily my icons. Since those are not 4.0 compatible yet it will take me forever to figure out how to arrange my icons with the new “folder” feature.

    Also I hope someone makes an app that allows you to fine tune multitasking settings per app. For instance I have some apps that I WANT to close when I leave them. They stay open for no reason.

  • Garcon3

    I downloaded the ios4 iphone3g fireware and extracted it and it was a dmg file and im a windows xp user, I changed the .dmg to .ipsw and the redsn0w does not recognise the file, I have no idea what do so pleaseee help

  • Rob

    If you are a windows user then you've gone wrong somewhere. iTunes itself will download an ipsw from straight from Apple. You don't need to change it's file extension. .dmg is a mac extension for your reference.

    Have another read then another go and I'm sure it'll come together.

  • Jrat1321

    After I've completed, I no longer have MMS

  • Rob

    Take the carrier update that iTunes offers. Or if O2 wait for 1010 to set you up. If still stuck we have details of servers.

  • Jrat1321

    I'm new, what is O2 and who is 1010? sorry

  • Rob

    Ah. You aren't a UK user then.

    Which country are you in?

  • Jrat1321

    US, I don't know how many times i've restored and jailbroken this phone, but i have MMS when i restore it, No MMS when I jailbrake it. Using the same IPSW

  • Rob


    Under settings you can manually set the mms options. You probably need to specify them if they aren't already populated. I have all UK network settings buy sadly not US ones. Sorry!

  • Rob UMM

    I upgraded my 3G to ios4 and have lost all my apps, photos and contacts etc.

    Also I had previously unlocked the phone onto the 3 network and now I don't have a network at all.

    Any ideas what I can do??


  • fer

    it means that if one choose iOS4 + jailbreak, then no more MMS?

  • Badilicious

    Dear Rob,

    I tried to update my Iphone 3G with the iOS 4.0 (as discussed before) and after many attempts, I decided to restore the phone through itunes 9.2 and with it get the iOS 4.0 version. It however failed and I now have a brick phone. I have multiple times tried to restore it, but it stucks at approx 20% and well thats it… it freezes!!!

    I've tried to install itunes on another laptop, have tried multiple time to go on DFU mode, I have deleted itunes, have tried to install another older version etc etc… and now I have just lost it. Since my contract has expired.. my carrier does not take it in for reperation nor do apple have an Iphone technical department (I am in Sweden).

    I've gone through a number of websites and tried all kinds of things, without any success and I am now finally asking you – to see if you have any clue of what I can do?

    Appreciate all the help and thanks for previous information!

  • RTj

    i got my iphone 3g updated and jailbroken. everything works well but the only thing that really bothers me is that i no longer have mms. my iphone is factory unlocked. do you have any solutions for me to fix that? thanks a lot!

  • Rob

    Very interesting you aren't the first to say this. Gonna raise this with the jailbreak team.

  • RTj

    i'd really love to have my mms back. i hope everything's gonna be great soon. please inform me. and do you know how to downgrade iphone to 3.1.3 ? thanks.

  • Rob

    I am sorry you are having so many issues. It's not normal to have such difficulty.

    Do you know if you were 3.1.2 or if you were 3.1.3 before your upgraded to iOS4?

    I'm going to suggest that you force a restore using older firmare.

    To do this put your iPhone in recovery mode, iTunes should detect the handset wanting recovery, browse to the IPSW for your older 3.x firmware and apply that.

    If you don't have the firmware then I will see if I can get you a download link from Apple.

  • Badilicious

    Thanks for your help.

    I was on 3.1.2 and hoped to upgrade directly to iOS4 – without any success.
    Before the phone went into the brick condition, I did a mistake and deleted itunes 9.2 and all its components include bonjour from my previous laptop and after re-starting the computer.. the system seems to have crashed and basically nothing works, it does not even detect the windows wireless service. Well, thats another issue…

    So to answer to your question.. no I dont have the old firmware. I am however using another laptop with itunes 9.2 and if you can find a downloadable link.. I would greatly appreciate it!


  • Rob

    That's a terrible experience.

    Here's the iPhone 3.1.2 firmware for the iPhone 3G direct from Apple:

  • Rob

    Apple say it'll illegal to download; however I can't see that standing up in court.

    Details here look like a workable solution:

    (Haven't personally tested)

  • Anthonypatrick326

    i am having the same issues, and i cannot figure out what the problem is

  • Rob

    It seems to be pretty common. Have notified the jailbreak team.

  • Badilicious

    Dear Rob,

    You are an absolute awesome person! Thank you indeed for your quick support! The phone is finally back in 3.1.2 firmware and it feels good that its working!

    I'm also wondering whats the easiet way to uppgrade to iOS4 and then jailbreak it? I've tried twice (after installing twice the 3.1.2 firmware), first by trying to restore the phone through Itunes 9.2 – but it stucks as before but at approx. 10%. I then tried to update the firmware, but the same thing occurs again! It does not go further than 10%.

    Any more great advice?

    Once again, I appreciate all the help and support! You are the man!!!

  • Rob

    Really pleased you are up and running again. Must be a huge relief!

    I haven't cone across the problem you are experiencing especially even with a stock image. I'm asking round mates who do similar iPhone stuff to me in case they've heard something I haven't.

  • Badilicious


    Do know from where I can re-install the ios4 firmware… any downloadable link ? I mean instead of installing it from itunes..

    Appreciate the help!

  • Rob

    Here's the official iOS4 ipsw for iPhone 3G right from Apple's servers:

  • Badilicious

    Dear Rob,

    Thank you for the link. I've downloaded it, but Itunes does not allow me to restore nor update the file. It says “itunes cant restore the firmware, because its not compatible” – Any idea what to do? I am on itunes 9.2!

  • Rob

    I have a feeling this is down to Apple not wanting you to “roll back”. I did see something earlier I replied to another comment with. Can't find link immediately as out and about. I do know there were some instructions in a website called lifehacker earlier today. Have a quick look there.

  • Badilicious

    Dear Rob,

    Thanks for your help so far!

    I downloaded the iOS4 firmware from the following site (…) and tried to restore the phone and for some reason it worked fine and I know have the ios4 update. For some reason the link you provided previously was over 500 mb while the one I luckily installed was 293 mb. Not sure if it matters..

    However, I am still eager to jailbreak the phone. Love the cydia apps and would like to know how I can jailbreak it, hopefully there will be a step-by-step guide aswell. I've tried the above redsnow jailbreak application… but fails, by telling “Unable to recognize the specified IPSW”.

    Once again… any idea how I can easily jailbreak the phone?

    The downloadable firmware is: iphone1,2_4.0_8A293_restore

    Biiiig Thaaaanks!!!

  • Rob

    Point redsnow to the ipsw you downloaded. If it's 3.1.3 then you'll need a different jailbreak method.

  • Badilicious

    Dear Rob, I did point the redsnow to the ipsw file I downloaded! It goes “Unable to recognize the specified ipsw”! I has before 3.1.2 and now iOS4!

    Appreciate ur help!

  • Rob

    You are pointing it at the iOS4 file aren't you? And is redsnow the one I linked to? Might be a new one on redsnow website.

  • Badilicious

    Dear Rob,

    Thank you indeed for all your help and quick replies! It was truly a relief when I was able to restore the phone from a brick condition and now I am just so happy, because I've got the iOS4 firmware and its also jailbroken. Its actually working better than before when I was on 3.1.2, it fast and absolutely great!

    Also I've noticed a number of people mentioning that there having issues with mms… but my one seems to be working perfectly! I believe they need to add the correct network settings to get it to work. The following website:… – seem to have many countries and operators APN and MMS Settings. Some probably needs to be updated, but it did work for me.

    Once again thanks a lot and may God bless you all!

  • Rob

    Really pleased and relieved to hear you are all sorted. Good job.

  • teban

    hey i tried everything but nothing seems to work to get mms back after jailbreaking 4.0 .

  • Amjad

    I have successfully Jail break and unlock my iPhone 3G after upgrading to iOS 4.0
    Now i am unable to enter the APN and MMS setting.
    Only Cellular Data Network ON OFF button is visible
    i cannot see the APN & MMS settings.

  • Phil

    Hi there,

    I've read your responses and love the attention you give. This is great, and I hope you can answer my simple question, as I'm not too sharp on all this.

    I have a 3G that was unlocked and upgraded to OS version 3.0 using software a while back. It works fine with iTunes etc.

    You mention that the methods on this page only work if you have “an active sim card for the network that your iPhone should be on, or have a factory unlocked iPhone since the iPhone will need to activate itself via iTunes.”

    How can I do the upgrade, and end up with an unlocked, jailbroken phone like I have now?

  • Rob

    Hi and thanks for the kind words.

    I'm assuming from your comment that you don't have a sim card for the network to which your handset is sim locked? If you can't borrow or get a Pay as you go sim, then the best way to jailbreak and sim unlock your handset is to do so using Pwnage Tool (for Mac) or Sn0wbreeze for PC. We've not got guides written up for these yet; however the reason we suggest them is they enable you to undertake a process called hacktivation. This basically means your handset is activated by the jailbreak as opposed to with an operator sim.

    Further reading can be found on sites such as


  • Rob

    As per the other comments in the thread, this seems to be a common issue and one we've alerted the jailbreak team too. We've no further update on this I'm afraid.

  • Rob


    Latest redsn0w should fix any APN/MMS issues (remember to deselect Cydia if it's already installed) (via @MuscleNerd)

  • Rob


    Latest redsn0w should fix any APN/MMS issues (remember to deselect Cydia if it's already installed) (via @MuscleNerd)

  • RTj

    hey thanks a lot for the updates. my iphone is now using iOS4. well, i have been using it for almost a week. and i see there's an update which fix the APN/MMS issue. so, can just go straight and do the jailbreak? thanks a lot.

  • Phil

    Aha. Thank you for that. All now done. Very cool.

  • coopergay

    Hi there,
    I bought a used iPhone 3G which had not been upgraded, therefore I was able to have it jailbroken (I'm in Canada). I am currently traveling in Italy and the phone died. It kept turning on/off, showing the apple logo. I tried to reboot and it went to the itunes image. Went to a “apple” shop (as it's jailbroken), they said nothing could be done, they can't even get it to charge. I was able to restore the phone on a mac desktop that's using iTunes 9.2. Of course, it's locked now and I'm sure I've lost all contacts, music and photos. Is there anyway to jailbreak the phone now or am I out of luck? I don't have access to a SIM that's compatible.

  • Rob

    If you have a Mac (which you mention in the text) then you should be able to build a custom IPSW using pwnage tool, however the sim unlock could well be a problem since your baseband will have been updated. There are ways to downgrade your baseband (tools from Cydia) such as Fuzzydowngrader, however they only work on certain handsets.

    Your best bet is to build a IPSW using an older, say 3.1.2 firmware, and apply that to your handset, then check and see if it's possible to downgrade your baseband since at the moment you won't be able to sim unlock with the latest firmware.

    It unfortunate, but your best option would have been to build a firmware, remove the baseband update from it and then apply that to your iPhone when it was in its duff state rather than using the stock firmware update. You would have had a more guaranteed success available to you.

    Good luck.

  • Jay

    Hey….i cannot do the jail broken process…..coz i cannot find the IPSW file in my computer….dunt kno w where it is located….i m using windows 7 ultimate….so does the location changes??????…..tell me about….

  • Rob

    Details are in the main post.

  • jay

    hey……i have done everything but i cannot open the apps now……wen i open cydia it also does not prompt me essential upgrades….

  • Rob

    Hard reboot. Press and hold both buttons til Apple logo on screen. Then when up do a full sync with your iTunes. Apps failing to open normally means your iTunes credentials have “fallen off” your iPhone. Failing that, start over.

  • jay

    hey man evrything is sorted out…….ur instructions were great…….a big thank you to u……

  • Rob

    No problem. Glad to have helped. I had that happen to me once and it took ages for me to suss it out!

  • B5251r

    not sure I have jailbreak and sim unlocked 3g with 3.0 firmware can I use this upgrade ?

  • Wisewildwicked

    Dear Rob,

    I have iphone 3G with firmware 2.2.1 – jailbroken and unlocked. Can I upgrade to the latest ios4? any risks?


  • Rob


    4.0.1 is what Apple are now signing as their latest version.

    You can update your iPhone 3G to this using the method I have detailed and jailbreak using redsn0w; however as standard you will not be able to sim unlock your handset because the baseband of the handset will be updated.

    If you have access to a Mac then you can build a custom ipsw file which doesn't update the baseband and then update, jailbreak and unlock.



  • Wisewildwicked

    Hi Rob,

    Many thanks for your reply. I'm not really bothered about sim unlock. I'm using O2 network and if I simply upgrade my iphone 3G with itunes to latest firmware, would the phone get locked? I just need to confirm that I would still be able to use my iphone as normal afetr upgrading it.

    Many thanks,


  • Rob

    You can update to the latest version no problem. You should be able to jailbreak it using redsn0w too.

    Just make sure before you install any Cydia apps that you check to make sure they work. There's a link to an updated spreadsheet in the main post.



  • Morepinzgauer

    I have a 3g 8g running on version 3.0. modem firmware 04.26.08. I would like to send it to the Philippines for a friend to use. what would be the easiest way to get it unlocked?

  • bb

    hi i have an iphone 3g unlocked and jailbroken and have been using it on tmobile network. i had done the upgrade for the ios4 software, now nothing works on the phone except emergency calls and i dont have an at&t sim to put in it. is it possible to use someone elses sim or buy a pay as u go phone and use its sim to get into the phone then unlock it? or what other method can be used to fix my phone?

  • Rob

    You are right. Use another sim for the approved network and it'll activate.

  • The easiest way to overcome such a situation (should it occur for you) is to unplug the iPhone, reboot your computer, open iTunes and reconnect your iPhone.

  • i tried jailbreaking my 2g itouch and i waited an hour when the computer said waiting for reboot so i disconnected my itouch and now it wont turn on help please?

  • please reply to me on twitter @1234skaterdude

  • Rob


    Sorry, I don't have a 2G handset, nor do I have any experience of the device to be able to offer you any help with it. Perhaps one of the readers can help you out. This article is for the 3G handset.

    Good luck!

  • Mahmoud Ijmail

    dear dev team, i hef iphone 3g update 4.0.1(8A306) i use dies ipsw iPhone1, en iPhone1, whit but i still get dis Unable to recognize specified IPSW please help me thanks.

  • Rob


    We aren't the iPhone dev team, but we'll try to point you in the right direction.

    Visit the redsnow website and download the latest redsnow beta, or alternatively, restore your handset and use the vastly improved jailbreak method we posted about a couple of days ago using

    See here:


  • Aryan

    Dear Rob,
    I have a jailbroken iPhone 3G that I was upgrading to 4.0.1 today, I didn't realize it was jailbroken through the “sim unlock” process. I am in a different country now and well…I won't let me activate it back without an AT&T sim card or basically any approved sim card. Is there anything you can help me with? Or am I just out of luck?

  • Ehtasham111

    Rob, i want to know that i have i have jailbroken my iphone3g and also unlocked it and i have old version and i wanted to update it to 4 can i update it

  • My version is 3.0.1 (ya..damn old)… modem firmware 04.26.08.. jailbroken and unlock im scarwd of doing those guide is it possible that if i upgrade to ios 4 only the version can change ? sorry im a filipina from phillipines 🙂

  • Kazza

    Hi – is this forum still active?

  • Monty_1689


  • Monty_1689

    i tried using another sim also but its not been fixed yet… and my phone is not working as well……. 

  • Rob

    I don’t respond to shouting comments (capital letters)

  • Monty_1689

    i m sorry for that… but i was in the office and and i always keep CAPS on because my work needs that…
    so i just forgot to do this…
    plz help me i m stunk with this…
    it states that insert the sim card which you got with this phone… but i dont have i m in Manila..
    and i got this phone in West Africa…Abidjan.. 

  • Rob


    Just looked at the title for this and can see that you are looking at an old article regarding an old version of the firmware. Can I suggest you look at this updated article of ours and see if that helps you?

  • Dazjones35

    Hi i have an iphone 3g with firmware 3.1.2 and baseband 06.15.00 i want to upgrade it to 4.0 I have the firmware on my pc but when i do the usual hold shift+restore with itunes the iphone just goes into a connect to itunes screen with an error message. Is there a way i can just update to 4.0 through cydia or another 3rd party app? Thanks

  • Rob

    Which firmware are you trying to put on there?

    4.3.5 is the latest and the only one Apple will now sign.

    Your only opportunity at installing an 4.x firmware other than the latest is if you’ve got an SHSH blob saved for a specific firmware you want to install. If you had Cydia installed on the 3.1.2 firmware it’ll display all blobs saved. The same information can be seen inside TinyUmbrella if you download and install that.

  • Anonymous

    Bundle of thanx for giving so complete guideline for Upgrading our iDevices………

  • You are genious maan

  • Rob

    No problem.

  • Rob

    Most welcome.

  • Patelvats1234

    It’s awesome!

    But I am facing problem that once I installed the application through cydia it doesnot show in settings
    What to do?
    Please reply.

  • Bhuvnesh Dev

    hey, i got iphone 3gs which is factory locked and now jail breaked wid version 3.1 so, i wanna upgrade to     i 4.. so iwant to ask dat if i update as ur procedure did it get locked again?

  • Rob

    Sorry. Could you write in English rather than colloquial text speak please? I have no idea what you are asking.

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