Untethered Jailbreak For iOS 4.2.1

Here’s what you will need to know before proceeding:

• iPhone, iPad or iPod touch running iOS 4.2.1
• iPhone, iPad or iPod touch with SHSH blobs saved for iOS 4.2 Beta 3.
• Mac OS X
• Access to iOS 4.2 Beta 3 firmware file.
• If you rely on an unlock, STAY AWAY from this version of Redsn0w.
• Currently limited to iPhone 4, iPad and iPod touch 4G only.

The best thing about this “backup plan” is that it doesn’t require you to restore or re-jailbreak your iPhone, iPad or iPod touch.

Here’s how to do it:

Note: Skip to Step 2 if you have previously jailbroken (tethered) your iOS device on iOS 4.2.1 with Redsn0w.

Step 1: Restore your iOS device to the official iOS 4.2.1 firmware and jailbreak it using Redsn0w by following our step by step guide posted here.

Step 2: This untethered jailbreak completely relies on SHSH blobs saved for 4.2b3 (iOS 4.2 Beta 3). To check whether you have SHSH blobs saved for iOS 4.2 Beta 3, start Cydia and wait for it to completely load the main page.

Step 3: Download Redsn0w 0.9.7 and connect your iPhone, iPad or iPod touch with Mac.

Step 4: Now download usbmuxd from here and extract it on your computer. Start Terminal inpython-client directory and then run the following commands as shown in the screenshot below

chmod +x tcprelay.py

./tcprelay.py -t 22:2222

Step 5: Start Redsn0w and point it to the official iOS 4.2.1 firmware file.

Step 6: Now click “Next” and select “Jailbreak Monte” option, followed by selecting iOS 4.2 Beta 3 firmware file.

Step 7: Now make sure your device is both OFF and PLUGGED IN to the computer before you click “Next”.

At this stage you will be presented with a screen where you will have to quickly hold “Power” button and then while holding the “Power” button, you will now have to hold “Home” button too. Now after few seconds release “Power” button but keep holding “Home” button until installation begins.

Step 8: Sit back and enjoy while Redsn0w will do all the rest for you. Once done, your iPhone, iPad or iPod touch will restart automatically and you will find it fully jailbroken (untethered) on the latest iOS 4.2.1 firmware.

If you want to see a video in detail demonstrating this process search for this video. http://www.youtube.com/watch?v=4CSEufUsdV4&feature=player_embedded