You will not lose your warranty, if you have not rooted S2. Before proceeding with the steps below, please make sure that you have backed up all your important data on the phone like calls, messages and apps, since your phone will be wiped clean of all data once the firmware is installed. Rooted users can use Titanium Backup to backup all their apps, and non-rooted users can follow this guide to partially backup their apps. Your data on the internal (16GB memory) or on the external SD card is safe, so no need to back them up.
Below are the required steps on how to update your Galaxy S II to Android 2.3.6 KL1 Indian firmware using ODIN -:
- Make sure you have KIES installed. This will make sure that you have all the necessary drivers installed.
- Download the official Android 2.3.6 XWKL1 Indian firmware from here. The password of the zip file is ‘samfirmware.com’ without quotes. Also, download ODIN from here.
- Extract the contents of the zip file inside a new folder on your desktop. There will only be one tar file inside the zip which you downloaded above with ‘I9100XWKL1…_Home.tar.md5′ as its name.
- Fire up ODIN, and then click on the PDA button. Now, select the I9100XWKL1 file which you extracted inside a new folder on your desktop.
- Switch off your Galaxy S2 (I9100) and re-insert the battery. Now, press the Volume Down + Home + Power button simultaneously to boot into Download mode. A warning will come up about your warranty being void. Simply press the Volume up button to skip it.
- Your Galaxy S2 will then display a yellow exclamation mark. Connect your phone to your PC, and ODIN will then detect it. When detected, ODIN will display a random COM No. in a glowing box in the ID:COM section.
- Now simply press the ‘Start’ button and wait for ODIN to flash the new firmware on your phone