Requirement Rooted Samsung Galaxy S5 G900M/G900/F/G900T [DON'T USE ON ANY OTHER DEVICE or VARIENTS ]
It is small utility to backup/Restore EFS for Smamsung galaxy NOTE 3 N9005.
Features
This tool simply Backup/Restore efs.img,modemst1 and modemst2 partitions. As we on qualcommdevice IMEI number no more stored on EFS partition so no meaning to make backup of only efs.img. you must have backup of modemst1 and modemst2 partition too. This tool will backup all three partitions.
Installation
-Needs Rooted device
-Enable USB debugging
-To make backup you needs to long press backup option icon, Backup files will be stored to MyEFS_mm_dd-yyyy-hr-mm_Device IMEI folder on Int SD card. This will make backup of all three required partition efs.img.ext4, nvrebuild1.bin and nvrebuild2.bin. Also you will found build.prop file in backup folder, which is just to get information about your ROMwhile backup was created.
-To restore, you have to first copy all three backup files (efs.img.ext4, nvrebuild1.bin and nvrebuild2.bin) to root directory of Int SD card. Once all three files there on int SD card simply long press Restore EFS option icon and reboot device.
Note : This application is not for just playing around, DON'T restore just to check/test application, Restore option must be used only when you really needs it.
If you don't know what is EFS and why you needs to restore, Don't use it. Read XDA thread for further info.
http://forum.xda-developers.com/showthread.php?t=2420881
We can't guarantee this will surely works on every case, you can use at your own risk. Also note that you can restore only backup which you have made on same device only.