Jailbreaking iPhone 3G (iOS 4.2.1)

I have a 3 year old iPhone 3G and for the past couple of months kept trying to jail-break it so that I could use the phone on any cell-phone network and was always having trouble.

I had tried limera1n and greenpois0n and both didn’t work on my 3G iPhone.

I finally tried Redsn0w today and managed to successfully jailbreak the phone.

Here are the instructions:

1. Download iOS 4.2.1 package (IPSW) for your iPhone 3G from Apple’s website
   http://appldnld.apple.com/iPhone4/061-9853.20101122.Vfgt5/iPhone1,2_4.2.1_8C148_Restore.ipsw
   For a comprehensive list of packages for other iPhone devices check out the following site:
   http://www.iclarified.com/entry/index.php?enid=750
   Note: You can use the above downloaded package to reinstall a fresh copy of the iOS 4.2.1 firmware to your phone. To do this you need to run iTunes and while your phone is connected, click on the update button while pressing shift. (This will let you browse to the IPSW file which you downloaded above).
2. Next you need the RedSn0w executable. Get it from the following link:
   Windows: http://cdn.nspwn.com/redsn0w_win_0.9.6b4.zip
3. Extract the files in the archive that you downloaded.
4. Right click on the redSn0w.exe file and open the Properties window. Select UNBLOCK.
5. Before running RedSn0w turn off any anti-virus you may have running temporarily (first scan the Redsn0w package before turning of auto-protection).
6. Run RedSn0w in administrator mode (Right click on RedSn0w.exe and select run as Administrator).
7. The first screen will have a browse button. Click on it and select the IPSW file that you downloaded in step 1.
   RedSn0w will process the IPSW file for less than 1 minute after which the Next button will be enabled.
8. Clicking on Next will process the file.
9. The only 2 options that you need are “Install Cydia” and “Enable Battery Percentage” (These are the default options).
10. Click Next.
11. Now before you hit Next on this screen read the instructions carefully. You need to prepare the device for unlocking
1. First make sure that your phone is on.
2. Connect it to your computer
3. Now hold the power button down until you get the Slide to power off screen
4. Slide the power off button and power down your phone (remember all this is done while your phone is connected to your computer).
12. Before clicking next here is what you need to know.
1. As soon as you click Next you will be asked to hold down the power button for 3 seconds
2. Next you will be asked to press the Home button without letting go off the power button for another 10 seconds.
3. Finally you will let go off the the Power button, but continue holding down on the Home button for 15 more seconds.
13. Now that you know what is going to happen next, click the Next button and follow the instructions (which will be similar to what I described in 12).
14. If everything worked correctly, RedSn0w will begin loading the modified firmware onto your phone and then reboot it.
15. After that the jailbreak process will continue on your phone.

To verify that you managed to Jailbreak your phone all you need to do is check the battery meter (top right corner and it should have a % value next to it. In addition you should see the Cydia app on the phone).

That’s it. Your phone should be jailBroken and you should be able to use it with other cell phone carrier’s sim card (like Sprint)

And if you are worried that Jailbreaking your iPhone maybe illegal in the US, don’t worry, Federal agencies have concluded that Jailbreaking your phone is legal. See: http://abcnews.go.com/Technology/us-government-jailbreaking-iphone-legal/story?id=11254253