Update Galaxy S2 I9100 to Jelly Bean 4.1.2 using RootBox ROM firmware

Ever since Google released an update for the Android Jelly Bean operating system, called 4.1.2, many users of the Samsung Galaxy S2 I9100 have wanted to know how to flash it to their handset. So we will tell you today how to get it on your phone.


All you need to correctly install the RootBox custom ROM created especially for the Galaxy S2 I9100 is a comp running the Windows OS, a image customized of your ROM, a backup of what is really important on your handset and a USB cable. The actions that you must perform once all of the above is verified are the following: turn the phone’s USB debugging on, turn all of the antivirus applications on your laptop off, check to see if the battery is fully charged and then if the Galaxy S2 comes with a minimum of 1GB of space of the internal memory card.

But you need to know that, once you install this custom ROM, the warranty of the device will disappear. Fear not: you can get it back if you don’t want to risk anything. The other option is to downgrade the actual version of your ROM file.galaxy-s2

Let’s see now what steps you need to follow in order to successfully update your Samsung Galaxy S2 I9100 to the Android 4.1.2 Jelly Bean with the RootBox custom ROM.

Important instructions

  1. First step: go online and look for . Once you find it, download the file there. Then , find something called Google Apps package and download it from here.
  2. For the second step you have to save everything you downloaded on the laptop or PC you are using. After the files are on it, connect the Galaxy S2 to your comp.
  3. Step 3 comes next; for it to be successful, you need to move the previously downloaded files yo the internal memory card of your phone and then disconnect the latter. To do this, take the USB cable off.
  4. Step 4 tells you to switch the device off; then enter it in the mode called Recovery.
  5. [sc name=”banner-jos”]When you find yourself in that mode, the fifth step asks you to employ the phone’s menu so that you can click on the options called Factory reset/Wipe data and Wipe cache partition.
  6. Up next is step number 6, which sounds like this: go back to the recovery mode by clicking on +++go back+++. After that opt for the installation of the archive from the SD card. For that you must opt for Choose ZIP from SD card option.
  7. When you are done, step number 7 requires the user to select the previously copied file from the phone internal memory card; after you do that, flash it.
  8. For step 8 you have to repeat the sixth step. This will help you install the Google Apps package.
  9. This will take you to the last step, number 9: opt for +++go back+++. Finally, select the option named Reboot system now.