How To: Jailbreak iOS 4.2.1 (Untethered) [Windows]

The Chronic Dev team has finally released earlier today their much anticipated jailbreaking tool Greenpois0n RC5 for Windows. Now you can jailbreak your iOS 4.2.1 device, untethered, and take advantage of everything the jailbreak world has to offer. To help you do that, we've created a little how-to so you can jailbreak your iDevice with ease. Check it out: What Devices This Works On

• iPhone 3GS, 4
• iPod touch 2G, 3G, 4G
• iPad

What You Need

• Windows XP or higher
• iTunes 10.1+
• Greenpois0n RC5b2 (download here)

Steps

• Download Greenpoison, save it on the desktop or somewhere you think you can find it easily.
• You should begin by backing up your iDevice; connect it to your computer, wait for iTunes to launch and hit sync as normal or right click on your device in iTunes and hit backup.
• Once that's complete, turn off your device, BUT do not disconnect it from the PC.
• Find your Greenpoison download (from step 1), once you've found it, fire up "greenpois0n.exe" as shown below.

• Now click the  "Prepare to Jailbreak (DFU)" button and follow the on-screen instructions, placing your device in DFU mode. Don't worry if the instructions go by too fast just follow along on your own pace. If you can't get it right the first time, you can always try again.

• Congratulations, if you successfully completed this stage your device is jailbroken; now wait for it to finish booting, connect it to your WiFi and launch the grey icon on the Springboard, titled "Loader".
• Install Cydia by tapping on the icon in the app and you're done!

Common Errors

• "The program keeps crashing on my Windows 7/Vista PC": Right click on "greenpois0n.exe", click properties, then go to the compatibility tab, check "Run this program in compatibility mode for:" and choose Windows XP Service Pack 2 from the drop-down list, hit ok.
• “My device doesn’t load the jailbreak and just sits there with a few lines of text on it!”: Restart your device (by holding the Power and Home buttons simultaneously) and try again. This jailbreak has a few bugs, so you may have to try a few times. I personally had to try four times for one device and seven for another. But hey, it’s worth it.
• “Nothing loads in the Loader application! How do I get Cydia now?”: This is because the GreenPois0n servers are overloaded. The simplest solution is to simply wait. However, we're hearing that you might be able to work around this (at your own risk), by using redsn0w directly to just install Cydia, and apparently also by uploading the required files directly to the loader. We'll update you as soon as we hear some more about this method.
• “Nothing loads in the Loader application! How do I get Cydia now?”: This is because the GreenPois0n website is overloaded. Unfortunately all you can do is wait and try again later, it's not your fault.

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