If you are one of those geeky types who frequently flash custom ROMs on their smartphone devices to get the latest updates and features, then the one-click tool is tailor-made for you. When flashing custom ROMs, kernels or other modifications, the EFS data containing the device IMEI information may get erased, which could disable network connectivity on your device.
Thanks to XDA senior member as i9000, the new one-click tool enables you to easily backup and restore the EFS data on any Galaxy S3 variant with a single-click of the button. You no longer have to worry about losing network connections on your favourite Galaxy S3 phone after installing the latest custom ROM based Jelly Bean updates.
- The hack tool and the instructions provided in this guide are applicable only for the international version of Galaxy S3 and will not work with any other device. Verify your device's model number by navigating to Settings > About phone.
- Your Galaxy S3 phone should be rooted before installing the EFS hack tool.
- Enable USB debugging on the phone through Settings > Developer options.
- Download and install the Samsung KIES software on your computer, which contains the required USB drivers to connect your phone to the PC. Download KIES.
How to Backup and Restore EFS on Galaxy S3 I9300 Using One-Click Tool
Step 1: Download EFS Backup tool from the XDA developers' official thread.
Step 2: Extract the contents of the downloaded EFS zip file to a desired location on your computer.
Step 3: Plug in the phone to the computer through an USB cable.
Step 4: Browse and select the EFS hack file that you downloaded in step 1.
Step 5: Double-click on the Backup_EFS file and follow the onscreen instructions to backup your Galaxy S3's EFS data to the computer, which will get saved in the same folder in the mountable image (.img) format.
If you are facing network connectivity problems or lost IMEI data on your Galaxy S3, just double-click the Restore_EFS file (the same file which you saved to the computer in image (.img) format), and follow the onscreen instructions to restore the EFS data successfully.
NOTE: Ensure that the EFS data is saved in a safe location, so that it can be reused any time later if required.
[Source: The Android Soul]