Galaxy S2 GT-I9100 recently got updated to the latest Android 4.1.2 ZSMSA official firmware via Over-The-Air (OTA) update. The new official update is also available for manual installation via Samsung KIES in select countries.
If you have already installed the latest Jelly Bean official firmware on your Galaxy S2, then root access to the device will be lost. In order to restore root access and regain full system access for installing third-party root apps, custom ROMs and system tweaks, you need to re-root the device once again using our step-by-step guide given below.
NOTE: As the rooting method used in this guide employs ODIN flash tool, the ClockworkMod (CWM) recovery is not part of the tool and needs to be installed separately.
IBTimes UK reminds its readers that it will not be held liable for any device damage during or after firmware installation. Users are advised to proceed at their own risk.
- The Speedmod Kernel rooting tool and instructions provided are limited to Galaxy S2 GT-I9100 model. Verify device model number by navigating to Settings > About Phone.
- Back up data and settings using recommended custom recovery tool such as ClockworkMod (CWM) or TWRP, as data wiping process is mandatory in this tutorial.
- Download and install correct USB drivers for Galaxy S2 GT-I9100 on computer.
- Ensure USB debugging mode is enabled on phone by navigating to Settings > Applications > Development or Settings > Developer Options.
- Double-check the device has at least 80% battery charge to prevent unexpected device shutdown (due to battery drain) while installing ROM.
How to Root Galaxy S2 GT-I9100 on Android 4.1.2 ZSMSA Jelly Bean Official Firmware
Step 1 - Download Speedmod kernel rooting tool for I9100ZSMSA firmware to your computer and extract the zip file.
Step 2 - Download ODIN v3.07 which is needed to root ZSMSA official firmware on your phone.
Step 3 - Power off the phone and boot it into Download Mode. To do so, press and hold the Volume Down, Home and Power buttons together until the construction Android robot icon with a triangle appears on screen. Then hit Volume Up to confirm entry into Download Mode.
Step 4 - Launch ODIN on computer and connect your phone to it, while the phone is still in Download Mode.
Step 5 - When the phone connects successfully, one of the ID: COM boxes will turn yellow with the corresponding COM port number. This process may take some time. So, leave it alone.
Step 6 - Choose the file that needs to be flashed or installed on your phone. This file is obtained from the extracted file in Step 1.
- Click 'PDA' checkbox and selectthe file 'CF-Auto-Root-jflte-jfltexx-gtI9500.tar.md5'.
Step 7 - In ODIN, ensure Auto Reboot and F. Reset Time options are selected.
Step 8 - Click Start button in ODIN and root installation process will begin, which would take just a few minutes to complete.
Step 9 - Once the root installation is completed, your phone will reboot into Recovery Mode automatically and install the root package files. At this point, your device ID: COM box will also turn green displaying a PASS message.
Step 10 - Finally, when the home screen appears, disconnect the phone from computer.
NOTE: If the device fails to boot into Recovery Mode automatically (as given in Step 10) and root your device, then repeat the entire procedure from start.
OPTIONAL: If the issue still persists, repeat the entire tutorial, but make sure that "Auto Reboot" option is NOT checked in ODIN. Then after installation (Step 9), do the following:
Step 11 - Remove the battery to Power OFF the phone forcefully.
Step 12 - Boot (turn ON your phone) by pressing Volume Up, Home and Power buttons together to enter Recovery Mode manually. This will initiate the root install process on your phone.
Samsung Galaxy S2 GT-I9100 is now rooted on Android 4.1.2 ZSMSA official firmware. Check for the SuperSU app in your apps list to verify.
To ensure the root package is installed correctly and working, verify with Root Checker app.
[Source: Droid Firmwares]