I put together this tool for those that have tried to modify their system unsuccessfully and bricked their device. You must be able to get your device into fastboot for this to work. The easiest way is to purchase a factory cable or make your own(a $15 purchase or a little bit of your time is better than a bricked device).
The .img's in this tool were made from a rooted device w/ the su binary in place. There is no need to re-root your device, however if you choose to erase cache and user data(not necessary but may be a good idea) you will need to re-install Superuser.apk to gain root.
1.) Download the version you want to use from the link below and unzip.
2.) Enable fastboot mode. Turn off your device then plug into your pc using a factory cable. If the device is recognized by adb then you can use this command:
adb shell su -c "reboot bootloader"
KFHD_SRT_v1.3.5- 7.3.0 (seperate option for restoring factory recovery)
KFHD_SRT_v1.3.0- 7.2.3 (separate option for restoring factory recovery)
I apologize for the size of this tool. The .img files used are rather large. If you want to use your own backup .img then download the lastest version of this tool from here. Just place your system.img inside images folder. It must be named system for option 1 or system2 for option 2
-separate option to restore factory recovery and boot now on v1.3.0
-flashing boot and recovery images now a separate option
-boot and recovery images inlcuded
-SuperSU and GoogleServicesFramework now included as system apk's
-New option for installing Googleservicesframework.apk
-downgrade method instructions(confirmed)
-new system partition backups for software v7.2.1
-vending.apk to phonesky.apk for newest version of play store
Instructions for downgrading to 7.2.1:
1.) Download boot and recovery imgs(these are backus from 7.2.1) from this LINK and place in the folder where you have access to fastboot or inside the KFHD_SRTool_v1.2 folder
2.) Use KFHD_SRTool_v1.2 to flash system.img.
3.) Erase userdata and cache
4.) Open a cmd prompt from the folder where you placed the previously downloaded .img's.
Use these cmds:
fastboot -i 0x1949 flash boot boot.img fastboot -i 0x1949 flash recovery recovery.img
Those who deserve our thanks:
kinfauns for the how to on backing up and restoring system software.
bazm60 for confirming the method above works.
hellocali626 for bringing to my attention the need to flash boot and recovery images for downgrade.