Jailbreak 4.2.1 Untethered with Redsn0w 0.9.7 iPhone 4, iPod touch 4G [How to Guide]

As promised, the iPhone Dev Team has released the necessary jailbreak tools which can untether the latest iOS 4.2.1 jailbreak on iPhone 4, iPod touch 4G, and iPad. Old-generation iOS devices already have untethered jailbreak on iOS 4.2.1.

For those who don’t know, Apple has already patched the untethered patch in iOS 4.2.1 update so it becomes tethered jailbreak on new-generation devices mentioned above. Being tethered jailbroken means that once your iPhone is successfully jailbroken, you’ll need to connect your iPhone to your computer if you ever need to reboot your iPhone or your iPhone loses battery charge. The updates Redsn0w 0.9.7 brings untethered jailbreak for those devices on iOS 4.2.1.
Below is the full step-by-step guide to jailbreak your iOS device using Redsn0w 0.9.7 and get untethered jailbreak immediately.
Requirements:
You will need to have access to the iOS 4.2b3 ipsw and your iOS 4.2b3 SHSH blobs saved. You also already need to be jailbroken on iOS 4.2.1. MAKE SURE YOU BACKUP BEFORE ATTEMPTING THIS AS IT IS A BETA!
Step One
Create a folder called Pwnage on your desktop and in it place:
- Xcode (also found on your Mac OS X Install DVD)
- MacPorts
- Usbmuxd
- RedSn0w 0.9.7b4
- iOS 4.2.1 (iPhone, iPad, iPod touch)
- iOS 4.2b3 *Only iPhone developers have legit access to this firmware

Step Two
Double click the Xcode dmg to mount it then double click the pkg to install the application.

Step Three
Double click the MacPorts dmg to mount it then double click the pkg to install the application.

Step Four
Open Terminal from Applications:Utilities then input the following. If asked for a password then enter your administrator password.

sudo ports install libusb

Once libusb has installed then input the following command: sudo ports install cmake

Once cmake has finished installing input the following command: sudo ports install pkgconfig

Step Five
Double click the downloaded usbmuxd archive to extract it.

Return to the Terminal window and input the following commands to install usbmuxd: cd ~/Desktop/Pwnage/usbmuxd-1.0.6

mkdir build

cd build

cmake ..

make

sudo make install

Step Six
Disconnect and then reconnect your jailbroken iPhone to the computer via USB. Make sure OpenSSH is installed through Cydia then input the following into the Terminal window:
cd ~/Desktop/Pwnage/usbmuxd-1.0.6/python-client/

chmod +x tcprelay.py

./tcprelay.py -t 22:2222

*Make sure to leave this running as you continue the tutorial…
Step Seven
Double click the RedSn0w archive to extract it. Then launch RedSn0w from the extracted folder.

Click the Browse button

Select the iOS 4.2.1 ipsw from the Pwnage folder on your Desktop and click Open.

Click the Next button to continue.

RedSn0w will now prepare the jailbreak data.

You will now be presented with a list of checkboxes.

Select Jailbreak Monte (untether) from the list of checkboxes. You will be asked to select the iOS 4.2b3 ipsw from the Pwnage folder on your desktop then click Open. Click Next to continue.

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

RedSn0w will now guide you through the steps to get into DFU mode. You can find more help with DFU mode here

Hold down both the Home button and the Power button for 10 seconds.

Release the Power button and continue holding the Home button until RedSn0w detects the device.

RedSn0w will prepare Jailbreak Monte files, exploit with Limera1n, Upload RAM Disk and Kernel, and Send Jailbreak Monte files.

Notice that during this time usbmuxd will facilitate the connection to your device.

RedSn0w will inform you when it has completed successfully.

Please note that this is a beta release, and upcoming versions will bring support for Windows users and will have built-in usbmuxd for easy process [Thanks iClarified].
Download Redsn0w 0.9.7b4 for Mac OS X
Download iOS 4.2.1 for iPhone, iPad and iPod touch
Download iTunes 10.1.1 for Windows / Mac OS X

UPDATE 1: [Video Guide] Redsn0w 0.9.7b4 has been released to Untethered Jailbreak Without the Need of ‘usbmuxd’ Process ,