Firmware Android

Samsung has pushed the official Android 4.4.2 KitKat to Samsung galaxy S4 a few days ago, after walking around this update, I have found that there is a problem while trying to change the CSC (product) code.
If you tried to change CSC by using cscselector app or terminal, you will not see any changes and the CSC will stuck in the default code.

I will show you how to change it easily

Requirements :

• Rooted galaxy S4 or any galaxy device.
• Installed root file explorer ES File Explorer or Root Explorer.
• Installed CSCSelector or Terminal app

In my case, I will change CSC code from DBT to BTU.

Instructions :

• Open ES File Explorer or Root Explorer and mount RW.
• Navigate to : System / csc / BTU / system / csc /
• Copy all the files on csc folder and go back to paste it in : System / csc /
• Accept Overwriting or replacing files.
• Use CSC selector app or Terminal method to change CSC to BTU.

Done !!!

Notes :

• WARNING : Changing CSC will delete all data on your device.
• This method will work only on ROOTED devices
• This will only work if your current firmware support Multi-CSC
• It might display "PreconfigUI does not support SingleCSC" if your current firmware doesn't support Multi-CSC.
• This method should work for many galaxy devices which running Android jelly bean and KitKat. 

Links :

• Android Terminal Emulator App HERE
• CSC Selector App  HERE
• ES File Explorer App HERE
• Root Explorer App HERE
• Region CSC code list HERE

IMEI is a unique identification number programmed onto your device and you can check the unique IMEI of your device by dialing *#06# or written on sticker under the battery. It is required in order to be correctly identified on a mobile network.
Without IMEI, you cannot make calls, send SMS or use mobile data.

EFS is a partition on the internal memory of your device which contain important data including the IMEI.
If the data in this partition gets corrupt, you will lose your IMEI

Requirements :
1. Samsung galaxy S4 device
2. "Android Terminal Emulator" app (Link below)

EFS Backing up Steps :
1. Open "Android Terminal Emulator" and type
Then enter
It will ask for root permission
Then enter
B.  For galaxy S4 all LTE and US variant Type :
Then enter

C.  For galaxy S3 all LTE and US variant Type :

dd if=/dev/block/mmcblk0p11 of=/sdcard/efs.img

dd if=/dev/block/mmcblk0p12 of=/sdcard/mod1.bin

dd if=/dev/block/mmcblk0p13 of=/sdcard/mod2.bin

Then enter

3. Backup the created files on your phone's internal storage to your PC or the cloud.

EFS Restoring Steps :
1. Send the files (Step 3) to the internal storage of your device
2. Open "Android Terminal Emulator" and type :
Then enter
It will ask for root permission
3.A. For galaxy S4 GT-I9500 Type :
Then enter
B. For galaxy S4 all LTE and US variant Type :
Then enter

C. For galaxy S3 all LTE and US variant Type :

dd if=/sdcard/efs.img of=/dev/block/mmcblk0p11

dd if=/sdcard/mod1.bin of=/dev/block/mmcblk0p12

dd if=/sdcard/mod2.bin of=/dev/block/mmcblk0p13 

Then enter

4. Restart your device
Done !
Notes :
~ It won't delete your data
~ Make sure you choose the correct cmd in restoring process
~ This method will work only on ROOTED devices
~ Backing up EFS partition is highly recommended for users who use the custom Roms
~ Use it at your own risk
~ This method won't repair your device if you don't have a backup of the EFS partition, but you can to try this How to Fix "Not Registered on Network"/Wrong IMEI for Galaxy S3/S4/Note2
~ Every device has unique partition, so you can't use this if you have backup file from another device

Downloads :
Android Terminal Emulator App HERE