Unlocking iPhone 3g and 3gs (4.2.1)

These are instructions on how to jailbreak your iPhone 3G and iPhone 3GS on the 4.2.1 firmware using RedSn0w for Windows

Before we get started Read this Warning Carefully.

If you have an iPhone 3GS with the new bootrom you will only be able to perform a tethered jailbreak at this time. This means you will need Redsn0w’s assistance to boot into your jailbroken device.


Create a folder on your desktop called Pwnage. Download the following files and place them into your Pwnage Folder.

Download the following Software Redsnow:

Click Here

Then you need to download the 4.2.1 Firmware:

3Gs Users Click Here

3G Users Click Here

Now you should see these files:

Step #2
***If you are already on iOS 4.2.1 you can skip this step.

Connect your iPhone to the computer and launch iTunes.

Select your iPhone from the list of devices on the left. Now hold down Shift and click the Restorebutton. Restore is preferred as it won’t create any wasted space on your iPhone.

Navigate to the Pwnage folder on your desktop and select the 4.2.1 firmware ipsw. Click the Choosebutton to continue.

Step #3
Once iTunes has finished updating your iPhone to the desired firmware open the Pwnage folder on your desktop and launch the redsn0w application from the redsn0w folder we extracted earlier.

**** Important if you are a Windows 7 or Vista user ****

-Right Click on the Redsnow application before you launch and Select “Properties

-Go to the “Compatibility” tab and Click to Check “Run this program in compatibility mode for

-Select “Windows XP (Service Pack 3)

Step #4
Once RedSn0w opens click the Browse button

Step #5
Select the 4.2.1 firmware ipsw we placed in the Pwnage folder on our desktop then click Open.

You will be asked if this device is a newer fixed model. If yours is then click the Yes button; otherwise, click the No button. At this time you can only perform an untethered jailbreak on the older model of 3Gs.  If you have a 3G don’t worry about this part.

Step #6
Once the firmware has been verified click the Next button to continue.
Step #7
From this window you can select the jailbreak options you would like.

Make sure Cydia is selected.

Also Select Install iPad Baseband. Click Yes when prompted to confirm your decision.

Click Next.

Step #8
Please plug your iPhone into the computer and make sure its OFF then click the Next button

Step #9
RedSn0w will now guide you through the steps to get into DFU mode.  Just follow the Instructions carefully in real time.  If you screw up don’t worry, just Click Back and try again.

Step #10
If you were successful in setting the DFU, RedSn0w will now download the iPad baseband if needed and your iPhone will reboot

Step #11
RedSn0w will then begin uploading the new RAM Disk and Kernel.

Step #12
Once this is complete you will be notified that RedSn0w is done. Click the Finish button. When your iPhone finishes rebooting (5 minutes or so) it will be jailbroken with Cydia on the SpringBoard.

If you have a newer iPhone 3GS and performed a tethered jailbreak you can use Redsn0w to help you boot back into your jailbroken device. Simply select Just boot tethered right now from the options window and click Next.

Step #13

If you are on T-Mobile remember to turn off 3G before starting…

Press to launch Cydia Installer from your SpringBoard.

Step #14
Press to select the Manage tab at the bottom of the screen

Step #15
Press to select the large Sources button

Step #16
If the ultrasn0w repo is not present press the Edit button at the top right of the screen. Otherwise, skip to Step #20.

Step #17
Press the Add button at the top left of the screen.

Step #18
Enter http://repo666.ultrasn0w.com/ as the source url and press the Add Source button.

Step #19
Once the source has been added press the large Return to Cydia button.
Then press the Done button at the top right of the screen.

Step #20
Press to select repo666.ultrasn0w.com from the list of user entered sources.

Step #21
Press to select ultrasn0w from the list of packages

Step #22
Press the Install button at the top right of the screen.

Final STEP!
Press the Confirm button at the top right of the screen.  After installation completes successfully press the large Restart Springboard button.

Now just insert the Sim Card of your Choice!

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