COMPLETE Guide to Unlocking & Jailbreaking iOS 4.2.1 on iPhone 3G & 3GS

[djmalice]

Step 1: Download iOS 4.2.1 for your iPhone (for iPhone 3G click here, for iPhone 3GS click here). Save it on to your desktop. It will be used later on.

Step 2: Open up iTunes 10.1 and select Restore/Update. iTunes will now download iOS 4.2.1 and install it on to your device. Ensure you allow this entire process to run through. Do not move on to the next steps until this process has finished.

(congrats, you have now installed iOS 4.2.1 on to your iPhone, next step now is to upgrade the baseband on your device to a version that can be jailbreakable and unlockable. Redsn0w will do this and it will jailbreak your device)

Step 3: Download redsn0w 0.9.6b (click here for Windows, click here for Mac)

Step 4: Extract redsn0w to your desktop. Go to the executable file and right click it, select ‘properties’, click the ‘compatibility’ tab and select ‘Windows XP Service Pack 2′, at the bottom select ‘run this program as administrator’ and now click ‘ok’.

Step 5: Double click redsn0w, Windows will ask you (if you have UAC controls set up) if you’re sure you want to run it as administrator, click ‘ok’.

Step 6: If you have a multicore machine (i.e. a pc/laptop that is dual core, core 2 duo, quad core etc) follow this step, otherwise skip to step 7. Do not skip this step if you have a multicore machine!

Press ‘ctl alt del’ on your keyboard and select ‘task manager’. Click on the ‘Processes’ tab and at the bottom select ‘Show processes from all users’. Now, in the list, scroll to redsn0w. Right click on redsn0w and select ‘set affinity’. Deselect all cpu’s except for one. Click ‘ok’ and exit the task manager.

Step 7: In redsn0w click on ‘browse’ and locate your ipsw file (the one you downloaded manually to your desktop). Redsn0w will not verify that this ipsw is correct. If redsn0w tells you it does not recognise the file simply delete the ipsw and redownload it. Chances are, the entire file has not downloaded fully, as happened to me. Otherwise, redsn0w will tell you that it has successfully verified the file.

Step 8: Select what you like in the next screen but ensure that ‘Install Cydia’ and ‘Install iPad baseband’ are selected. These two are an absolute must.

Step 9: Click next. This screen tells you make sure your phone is plugged in and switched off. Make sure that your phone has been switched off whilst it was plugged in. If not, plug your phone in whilst it is switched on and switch it on whilst plugged in. Only then, can you select next.

Step 10: As soon as you click next you must follow the on screen instructions word for word. If you do this properly redsn0w will go through the motions with your device. Your iPhone will reboot a couple of times, then you will see some action o your iPhone display. Whatever you do, do not unplug your phone until it has fully rebooted and brings you to the home unlock screen.

(congratulations, you have now jailbroken your device as well as upgrading the baseband to a version that can be successfully unlocked)

Step 11: Now, on your iPhone menu, go to settings, select WiFi and put in your wireless settings.

Step 12: In your iPhone menu screen locate and select ‘Cydia’. Cydia will show ‘Initializing Filesystem’. It will automatically exit once done. Once it has exited and brought you to your lock screen open up Cydia once again. This time it will say ‘Who Are You’. Make sure you select ‘User’ and select ‘done’ in the upper right hand corner. Cydia will then download packages and its database. Let it do this, regardless of how long it takes. Do not cancel it or exit the application. Allow it to complete.

Step 13: Cydia will now pop up with an upgrade request box. Selext ‘complete upgrade’. Then select confirm. Once you’ve tapped confirm you will be brought to a black screen which will show you in verbose mode the upgrades installing. This may take a while but do not worry. Once installed it will ask you to ‘reboot device’, tap this and way for your iPhone to reboot.

Step 14: Once your iPhone has rebooted go back in to Cydia. Allow it to load, again this may take a while but do not worry. Once it has loaded tap ‘Manage’ at the bottom. Then tap ‘Sources’. In the sources menu tap ‘repo666.ultrasn0w.com’. This will bring up ultrasn0w, tap this and select ‘install’ and ‘confirm’ in the upper right hand corner. After this has installed you will again be prompted to reboot your device, tap reboot.

Congratulations! You have now installed iOS 4.2.1, upgraded your baseband (to allow your device to be jailbroken and unlocked), then you jailbroke your device and then last of all you unlocked your device to work on all sim cards on all networks and carriers!

taken from http://http://politicalpundits.co.uk...iphone-3g-3gs/

[KDR]

this helped me out a lot, thanks

[dallax]

[B

Step 4: Extract redsn0w to your desktop. Go to the executable file and right click it, select ‘properties’, click the ‘compatibility’ tab and select ‘Windows XP Service Pack 2′, at the bottom select ‘run this program as administrator’ and now click ‘ok’.

forgive my question.
What if I don0t have XP and instead have windows 7 64 bit on my machine?
Should i do something different?

[hexland]

forgive my question.
What if I don0t have XP and instead have windows 7 64 bit on my machine?
Should i do something different?

It's the same steps, I believe. Right click on the redsn0w exe and go to "properties > compatibility"...
select 'Run this program in compatibility mode for...' and select 'WinXP Service Pack 2'
select 'Run this program as administrator'
Hit OK

When you run the redsn0w exe (before doing anything with it)... right click on your task bar, and select 'Start Task Manager'

In the task manager... select the 'Processes' tab along the top, and locate 'redsn0w.exe' from the column 'Image Name'. Right click on it and select 'Set Affinity'
In the 'Processor Affinity' dialog, DEselect all but one CPU 0.

Hit OK, then close the Task Manager.

If you run redsn0w again, you'll need to do the 'Set Affinity' set again... this only affects the currently running instance - so if you close it down and start it again, it will go back to running on all CPU's

[Ben718]

if your iphone 3gs has the new bootrom and you wanna unlock it via redsnow make sure you do not update to 4.2.1 if you want untetherd jailbreak iphone on 4.1 using limera1n or greenpois0n and then load up redsnow and just install ipad baseband nothing else and your iphone will be untetherd

[miladjuckel]

guys has anyone actually tested the new software, are there any bugs on it like missed calls or slow text etc. cause i'm 4.0 and happy, i rather not upgrade yet if theres lots of bugs on it.
any ideas?

alright guys i went ahead and upgraded and got stuck on the last step using redsnow cause the ******* thing would constantly say waiting for reboot well that's because i skipped step 4-6 so make sure u do them otherwise the **** won't work, other then that everything seems to be working fine so far, but we shall see
good luck guys

[norman505]

does anyone have battery draining problem or gps with this method?
thanks in advance

[i.Annie]

There is a risk of gps loss with upgrading to the iPad baseband, Norman, so some users have experienced this. Battery drain is also expected, SAM will fix it. Download it from Cydia and google a guide on using SAM.

Note to all users: this method is tethered for new boot 3GS owners. Also, if you have a still unlockable baseband (5.13.04 and below) you should not take this route, you should avoid the baseband update to 6.15.00. Use PwnageTool method.

[virenxxx007]

i update to 4.2.1 and my sim is blocked what to do? the following error came on itunes "Only Compatible sim card from a supported carrier may be used to activate iphone. please insert the sim card that came with your iphone or visit a supported carrier's store to receive a replacement card"
and in i phone seems a itunes's logo and usb's logo shown in it.

[dallax]

There is a risk of gps loss with upgrading to the iPad baseband, Norman, so some users have experienced this. Battery drain is also expected, SAM will fix it. Download it from Cydia and google a guide on using SAM.

Note to all users: this method is tethered for new boot 3GS owners. Also, if you have a still unlockable baseband (5.13.04 and below) you should not take this route, you should avoid the baseband update to 6.15.00. Use PwnageTool method.

Hi,
I need to unlock an iphone 4.2.1. However, I do have a carrier sim that will allow me to activate the iphone.
Would you still advise me to use SAM after I have jailbroken the phone?

thanks

[i.Annie]

No if you have the carrier SIM, you should use that to activate and then jailbreak after activating. No need for SAM.

[belebartok]

thanks so much for your guide, very helpful. for those who can't find a custom ipsw for redsn0w, i used the stock one from itunes... just search for ipsw in explorer (or whatever in osx). hopefully that helps...

[jsa1189]

Hi,
My iphone 3g, version 4.2.1 with 05.15.04 firmware is already jail broken. All I want is for it to be unlocked so I can use T-mobile service on it, as well as picture messaging. When I go to cydia, sources, repo666.ultrasn0w.com, install, then confirm, it says size mismatch, then asks me to restart springboard. I have no idea what to do, so any help at all will be greatly appreciated.


Than You

[i.Annie]

You can't unlock that baseband. Follow the directions on this thread in the original post.

[dallax]

No if you have the carrier SIM, you should use that to activate and then jailbreak after activating. No need for SAM.

thanks i.Annie.
To clarify. I do have an original carrier SIM. However, I would need to use the iphone with another operator, so I will still need to unlock the machine.
Given that SAM fixes the battery drainage issue, would you still not advise me to run it before I unlock?

thanks again

[belebartok]

SAM only had to do with activation or, if you DONT have the official carrier sim, hacktivation. Since your phone was officially activated with the sim card you should have no problem with battery and push and therefore no need for SAM. if you run a restore and end up with the emergency screen, make sure to activate your phone officially
with your sim instead of letting redsn0w (or whatever) hacktivate it
ps: I am by no means an expert, but I have no intention of misinforming anyone. If I'm wrong about anything in this or any other post, I hope someone would let me know.

[i.Annie]

You're very correct. SAM isn't needed regardless of unlocking or not. It is only used when people hacktivate. If you're not hacktivating and you're using an official SIM, SAM does nothing for you.

[dallax]

There is a risk of gps loss with upgrading to the iPad baseband, Norman, so some users have experienced this. Battery drain is also expected, SAM will fix it. Download it from Cydia and google a guide on using SAM.

Note to all users: this method is tethered for new boot 3GS owners. Also, if you have a still unlockable baseband (5.13.04 and below) you should not take this route, you should avoid the baseband update to 6.15.00. Use PwnageTool method.

I am aware of SAM being used for hacktivation.
However in the above post i.Annie mentioned that it will also fix the battery drainage issue found with upgrading to the iPad baseband.
So, despite the fact that I don't need hactivation, I was wondering if I should run it before I unlock with the ipad baseband

[Simon]

It fixes the battery issue because it fixes the hactivation issues. If you dont need to hactivate then you dont need SAM. It wont help you in any way if you are activating with a official carrier sim.

[i.Annie]

To break it down, the battery drain is caused by hacktivation. If you're not hacktivating you won't have the battery drain. Therefor there's no point in using SAM.