How to Root Galaxy S2 ICS 4.0.3 Using ODIN and SuperOneClick
This blog post and the associated video shows you how to root your Samsung Galaxy S2 Android smartphone which has loaded with ICS 4.0.3 using ODIN and a useful software called SuperOneClick. To satrt the rooting process, you've to download these three files from the links provided.
1. CF-Root-SGS2_XW_XEN_LP7-v5.4-CWM5.zip - Download
2. Odin 1.85 - Download
3. SuperOneClick - Download
Make sure you have the Android debugger (SDK developer kit) running (If you're not sure how to install and run SDK developer kit, refer this post). Also the the USB drivers for your phone must be installed. After downloading those files, extract contents of 2 & 3 (Odin and SuperOneClick) into a folder.
1. Enable USB debugging by going to Settings > Applications > Development on your phone.
2. Turn Off the handset and switch on into download mode. For this pressVol Down + HOME + Power buttons together.
3. Once it boot into download mode, open odin by double clicking Odin3 v1.85.exe and connect the USB cable between your PC and phone.
4. In odin, click PDA and browse the CF-Root-SGS2_XW_XEN_LP7-v5.4-CWM5.zip that you've downloaded, also uncheck the Re-partition option the odin window.
5. Click Start and the process will be completed in few seconds. When the phone is rebooting, close odin and open SuperOneClick.
6. When the phone is booted to normal, click Root.
You're done!. enjoy root access. Checkout this video tutorial.