Root Android 4.1.2 ZSMSA Jelly Bean Stock ROM for Samsung Galaxy S2 I9100

Samsung has released a new firmware of Android 4.1.2 Jelly Bean with its version set to ZSMSA. Users who applied this update for their Galaxy S2 I9100 can now use this tutorial in order to successfully apply root. Read the entire post and you will be able to complete the root process in no time.
Rooting your smartphone allows you to add new custom ROMs and other customization files that should improve your Jelly Bean experience. Also, after you root the device, you should know that you can use a custom ROM based on Android 4.2.2 or even Android 4.3 to test some features and functions that will never be available as stock updates for your Galaxy S2.
In order to successfully root your smartphone you should first take a look at the preparation guide below:

• Use this post only for the Samsung Galaxy S2 International variant with model number I9100.
• Do not try to root any other Galaxy S2 variant with the files you find here.
• Download and install the Samsung USB Drivers for your Galaxy S2 I9100 from here.
• It would be best for you to create backups of all the important files that are currently stored on your computer.
• Enable USB Debugging from Developer Options menu.
• Disable or uninstall the Samsung KIES software before starting the root, as this app will surely interfere with the rooting process.
• Disable all antivirus / security programs.
• Verify the Galaxy S2 battery power level and make sure that it is over 50%, so that it will prevent the device from switching off while root is applied.
• Use this tutorial only if you’re an advanced user and you know what you’re doing, as you can end up bricking the device.
• In case the root is applied, but the device refuses to boot into normal mode, then you will be forced to apply the factory reset. This will remove all contents from your device’s system partition, but it will force the Galaxy S2 to boot with the rooted firmware. More info listed at the end of this post.
• Read the entire post and don’t skip any steps that I have listed below.
• Do not blame us in case you lose any important files or you brick the device in the process.
• If you cannot complete the tutorial, then you should ask for more help in comments.

How to root Samsung Galaxy S2 I9100 on Android 4.1.2 ZSMSA Jelly Bean:

1.  Download ZSMSA Android 4.1.2 root package from here.
   - save the file on your computer without extracting it.
2. Download ODIN 3.07 from here.
   - this file is the one that we will use in order to flash the root.
   - save ODIN on your computer and extract its contents to a single folder that should be saved on your desktop for easier access.
3. Power off the Galaxy S2 now.
4. Boot the phone into Download Mode.
   - it can be done by pressing and holding Volume Down, Home and Power buttons at the same time.
   - release the buttons when the Warning screen appears, then press Volume Up to confirm that you wish to boot Download Mode.
5. Next, launch ODIN 3.07 exe on your computer.
6. Use the USB data cable to connect your Galaxy S2 with your PC.
   - wait for ODIN to say that the device has been ‘added!!’
   - if the SGS2 isn’t recognized by ODIN, then you should switch between USB ports or try to re-install the Samsung USB Drivers (the download link is listed above in the preparation guide).
7. Go to ODIN window, click on PDA button and load the file downloaded at step 1.
   - make sure that the Re-partition box is not enabled.
   - do not change any other default Odin settings.
8. Press the Start button whenever you’re ready for the root to start.
   - do not press any buttons while the root process is in progress.
9. When the Galaxy S2 ZSMSA Android 4.1.2 firmware is successfully rooted your device will restart and start to load all the new rooted ROM.
10. Take control over your device, go to Google Play Store and download Root Checker basic app – link here.
    - launch the app and verify that the root has been applied.
11. That’s it, now you can flash a custom Recovery such as TWRP or CWM in order to be able to flash new custom ROMs.

In case ODIN freezes or the root hasn’t been applied for any particular reason, then you should disconnect the device from computer, close ODIN, remove the phone’s battery, re-insert the battery after a few seconds, re-launch ODIN and boot the device into Download Mode. Repeat the entire tutorial starting with step 6.
If ODIN says that the root has been successfully applied, but the phone doesn’t go past the Samsung boot animation (note that this might show for ten minutes straight without finishing the boot), or it enters into a boot loop, then you will be forced to apply a factory reset. This will force the device to boot into normal mode, but it will also remove all system files. The factory reset won’t remove data from internal / external cards.
Here’s how to apply factory reset for Galaxy S2 in case the rooted firmware doesn’t boot into normal mode after you finish the tutorial:

• power off the device, remove its battery and re-insert it back into its place after five seconds pass by.
• press and hold Volume Up, Home and Power buttons until the Recovery Mode screen appears.
• select ‘wipe data/ factory reset’ option and confirm this process.
• return to the main Recovery screen when the Factory Reset is complete.
• select ‘reboot system now’.
• wait for the Galaxy S2 to boot into normal mode and enter your Google Account details when the home screen appears.

These were all the steps that you had to take in order to apply root for your Galaxy S2 International.
If you want to flash a custom Recovery such as CWM or TWRP, then you should that you can use ROM Manager or Goo Manager apps.
The ROM Manager app can be downloaded from Google Play Store – link here.
- launch the app and then use the installation button to flash CWM Recovery.
The GooManager tool Google Play Store link here.
- launch the app and then press the ‘menu’ button and select Install OpenRecoveryScript.
If you have any other questions, then you should ask for more help in comments below.
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