Here is the step by step guide for Windows users to apply untethered jailbreak on iOS 4.2.1 devices while using Greenpoison RC5. Greenpois0n Windows version jailbreaks all idevices except Apple TV2, which will supported in the next update.
It is to be noted that Greenpoison also available for Mac Users. The whole guide and steps are same as mentioned in this guide. If you are a Mac User, simple download the latest Greenpois0n RC5 on your Mac machine and follow the same guide to jailbreak your device.
There are four types of users right now who are interested to get untethered jailbroken state on their devices:
a) Users having idevices on iOS 4.2.1 but without previously jailbroken – You can try Greenpoison without restoring to fresh iOS 4.2.1.
b) Users having already jailbroken devices on iOS 4.2.1 with (Redsn0w) Monte technique – Please restore to fresh stock iOS 4.2.1 first before jailbreaking with Greenpoison.
c) Users having idevices which are jailbroken (tethered) with Redsn0w – You can also try Greenpoison without restoring to fresh iOS 4.2.1.
d) Those user who fall into any of above categories but also rely on unlock – You can give a try to Greenpoison without restore to get untethered jailbreak. In case you fail, please restore to custom iOS 4.2.1 cooked with PwnageTool while preserving the Baseband and then use Greenpois0n.
Here is the complete step by step guide to jailbreak iPhone 4, iPhone 3GS, iPhone 3G, iPod Touch 4G, iPod Touch 3G, iPod Touch 2G and iPad on iOS 4.2.1.
Step 1: Back up your iPhone / iPad / iPod touch using iTunes.
Step 2: Download Greenpois0n for Windows.
Step 3: If you need to restore/update your device to iOS 4.2.1, use the latest version of iTunes to do so. Those users who rely on unlock will have to put their devices into Pwned (limera1ned) DFU mode before restoring to custom iOS 4.2.1. They can use Redsn0w to get Pwned DFU mode.
Step 4: Close iTunes and launch Greenpoison.
Step 5: Click on the button “Prepare to Jailbreak (DFU)”
Step 6: Greenpois0n will display the instructions to put your device into DFU mode.
- Press and hold the sleep button for 2 seconds
- While holding Sleep button, press and hold Home button for 10 seconds
- Release the Sleep button but continue holding Home button for 15 seconds
Step 7: Once your iPhone is in DFU mode, click the “Jailbreak” button.
Step 8: Greenpoison will now jailbreak your device.
Step 9 (i): After a successful jailbreak, your device will restart and you will notice a new “Loader” app in Springboard. Launch it and select Cydia to install it.
Step 9 (ii): If you are unable to install Cydia or you are on unsupported carrier and stuck at Emergency Mode, use Redsn0w to install Cydia and to hacktivate your device.
Enjoy jailbroken (untethered) device!
Update: An updated version of Greenpoison is now also available which includes iBooks fix. Read the post here for more details.