This guide will show you how to jailbreak iOS 4.2.1 on iPhone 3G/3GS/4 and iPod Touch using Redsn0w 0.9.6b4.
Note: You CANNOT unlock your iPhone. Stay away from this if you rely on an unlock. This also requires the new version of iTunes 10.1 to install 4.2 (4.2.1) on your iDevice.
Redsn0w brings untethered jailbreak for the following iDevices:
- iPhone 3GS (with old bootrom)
- iPhone 3G
- iPod Touch 2G (non MC)
Redsn0w brings tethered jailbreak for the following iDevices:
- iPhone 4
- iPhone 3GS (new Bootrom)
- iPod Touch 4G
- iPod Touch 3G
- iPod Touch 2G (MC)
STEP 2: Upgrade/Restore to iOS 4.2.1 via iTunes 10.1 (iPhone users: iOS 4.2.1 will update your baseband which is NOT unlockable right now).
STEP 3: Launch Redsn0w 0.9.6b4 and find your way to iOS 4.2.1 and click “Open”.
STEP 4: Select “Install Cydia” and click “Next“. You can also select the optional choices if you like (read STEP 7 for how to boot tethered iDevice).
Note: Make sure your device is both OFF and PLUGGED IN to the computer.
STEP 5: Follow the on-screen instructions.
STEP 6: Now sit back and relax while Redsnow does the thing it does best, jailbreak your iDevice. After the process is complete, your iDevice will reboot and you now have a jailbroken iOS 4.2.1 iDevice.
STEP 7: How to boot tethered jailbroken iDevice (iPhone 4, 3GS (New Bootrom), iPod Touch 4G/3G/2G (MC), iPad) after reboot, select “Just boot tethered right now”.