Earlier today we saw Apple’s iOS 4.2 going live for all iOS devices and in less than a day’s time the Dev Team has released a Jailbreak supporting all devices. Redsn0w has been updated to Jailbreak iOS 4.2.1 and is now available for both Windows as well as Mac.
This guide will help you jailbreak any device. However, let me first warn iPhone owners relying on Ultrasn0w unlock. An unlock hasn’t been released yet for iOS 4.1 or 4.2 and it will be available only after Cydia has been updated to 4.2(in a week’s time maybe). So at the moment you should refrain from upgrading to 4.2.1 and not use this guide.
The Redsn0w Jailbreak will offer a tethered or untethered jailbreak depending on the device you own:
- ?iPhone3G, older iPhone3GS, and non-MC iPod touch 2G: untethered jailbreak
- More recent devices (iPhone 4, iPad, iPod touch 4G): tethered jailbreak (meaning if your device reboots, you?ll have to re-jailbreak)
Steps to Jailbreak iOS 4.2.1:
1. First update your iPhone to the latest firmware by downloading the IPSW file using direct download links here. Use the direct download link as you will require the IPSW file during jailbreak in the later steps.
2. Open iTunes and press Shift + Update(windows) or Alt + Update(Mac) and point to the IPSW file to update device.
3. Download latest Redsn0w for your operating system:
4. Extract and run Redsn0w.
5. Click on browse and point to the IPSW file and hit Next. Once Redsn0w has prepared jailbreak data select “Install Cydia” and proceed with the onscreen instructions.
6. Hit Finish once Jailbreak is over.
In case your device falls in the Tethered Jailbreak category, you will need to repeat the steps with “Just Boot Tethered Right Now” selected. If you don’t do this Cydia won’t work yet. For Untethered devices, the magic is all done.
For tethered devices, it is a little exhausting to repeat this process every time the iPhone restarts but at least we do have an early Jailbreak.
In case you run into an issue do feel free to leave us a comment. Happy Jailbreaking!