Samsung just recently rolled out to the Samsung Galaxy S2 GT-I9100 a new Ice Cream Sandwich update known to the community as the XWLPD build. For those of you who have just flashed the recent firmware, you may already know that flashing official ROMs such as the XWLPD firmware will mean losing your root privileges.

Luckily for Galaxy S2 owners, XDA Developers member Chainfire has already made an exploit that will allow you to root your phone, as well as install ClockworkMod Recovery using the CF-Root Kernel. The kernel is fully stock and is primarily based on the original firmware, with some added features. The CF-Root Kernel has root access, BusyBox 1.16.2, and ClockworkMod Recovery.

Learn more about rooting and installing this modified kernel by checking our step-by-step guide below.

Warning

• The instructions in this guide are intended for use with the Samsung Galaxy S2, model number GT-I9100. Applying these instructions on another device or model may produce undesired outcomes.
• The information in this guide is provided for instructional and educational purposes only. There is no guarantee that these instructions will work under your specific and unique circumstances.
• Use these instructions at your own risk. We shall not hold any responsibility or liability for whatever happens to you or your device arising from your use of the info in this guide.
• Read and understand the whole guide first before actually performing the instructions.

Requirements

• Samsung Galaxy S2 GT-I9100 running stock Android 4.0.3 ICS build XWLPD
  • If you have not updated yet, check our guide on how to upgrade your Galaxy S2 to firmware XWLPD.
• A Windows PC
• Samsung USB device drivers for the Galaxy S2 installed on your PC. You can use Samsung KIES to obtain the drivers.
• Temporarily disable Samsung KIES, anti-virus tools, and firewall programs as they are known to interrupt the installation process.
• Enable USB Debugging on your phone. You can do this by heading to Settings > Developer Options > USB Debugging. Make sure that there is a check mark beside that option.
• Backup all personal data on your phone to make sure you have a copy of your personal data (e.g., contacts, SMS, MMS, Internet settings, Wi-Fi passwords, and the like) in case the procedure in this guide erases such data.
• • For backup tips, check our guides on how to sync your data to the cloud and how to create local backups of your mobile data.

Instructions

1. Download the CF-Root Kernel (CF-Root-SGS2_XX_NEE_LPD-v5.4-CWM5.zip, 6.2 MB) package to your computer.
2. Download Odin3 1.85 (Odin 1.85.zip, 200 kB) to your computer.
3. Extract the downloaded CF-Root Kernel ZIP file using any extracting software such as WinZIP or 7-Zip. Place the extracted file inside a single folder. Important! Do not extract the TAR file.
4. Extract Odin 1.85.zip and place the contents inside a single folder.
5. On your PC, launch the Odin3 application by double-clicking Odin3 v1.85.exe.
6. Switch off your Samsung Galaxy S2.
7. Boot your phone into Download Mode. You can do this by pressing and holding down the Volume Down, Home, and Power keys together until you are greeted with a Warning! screen. Press the Volume Up key to enter Download Mode.
8. Connect your Galaxy S2 to your PC via USB cable. You should see a message “Added!” under Odin’s message box found on the bottom-left of the application. This should indicate that your phone’s USB drivers have been installed.
9. In Odin3, click the PDA button, then browse for the CF-Root-SGS2_XX_NEE_LPD-v5.4-CWM5.tar file. Make sure that Repartition is not checked.
10. Important! Do not make any changes in Odin aside from the one’s mentioned in this tutorial. Doing so may cause irreversible damage to your device.
11. Select the Start button in Odin to begin flashing the CF-Root Kernel on your Galaxy S2.
12. Once the firmware has been installed, your phone should automatically reboot. A “PASS” message with a green background will be shown on the top-leftmost box of Odin.
13. Disconnect your phone from your PC once you see the Samsung logo.

Congratulations! You have successfully rooted your Samsung Galaxy S2 GT-I9100 using Odin3. Enjoy the benefits of having a rooted device.