[Samsung Galaxy J7 (2017) Questions & Answers] death.by.confusion:
[GUIDE][J730X] A beginer's guide to installing custom ROM on Samsung Galaxy J7 2017

In order to install a custom ROM, the general steps are to: Unlock bootloader, Install custom recovery, make a backup of your current stock ROM, and then go to install a custom ROM.

NOTE: It is good idea to note your software version and your baseband version right now(enter *#1234# on dial pad)

This is so you can find your stock ROM on https://www.sammobile.com/ and flash with Odin tool.

Unlock bootloader

In our samsung phone it is very easy to unlock the bootloader. All you have to do is go to Developer options and enable OEM Unlock(something similar to the image below)

[IMG="OEM Unlock screenshot"]https://www.goandroid.co.in/wp-content/uploads/2018/07/1OEMUNLOCK_preview-498x1024.jpeg[/IMG]

To enable Developer options, you go in About phone, and press on the field Build Number multiple times(something similar to the image below)

[IMG="Enable Developer options screenshot"]https://i.ytimg.com/vi/64xf-hdLIak/hqdefault.jpg[/IMG]

Install custom recovery

There are multiple choices for custom recovery for our samsung phone. I recommend to install TWRP 3.3.0(link here https://github.com/ananjaser1211/android_device_samsung_jxy17lte/releases)

You need samsung USB drivers(link here https://developer.samsung.com/mobile/android-usb-driver.html and the

the Odin tool(for flashing the recovery)(link here https://odinflashtool.com/download/odin3-v3-13-1/

1. Turn your phone in to Download mode. For that, first power off your phone, and then hold POWER button together with volume DOWN and HOME button, then connect the phone with USB cable on the computer.

2. Open Odin tool

3. In the options tab, uncheck auto reboot

4. Select the custom recovery image in to AP field(the exact file name of recovery from link is TWRP-3.3.0-j7y17lte-20190417.tar

5. Start flashing.

6. Now, hold POWER, volume DOWN, volume UP and HOME button together until your screen on the phone goes back, then instantly hold POWER, Volume UP and HOME button together, so you boot in to the installed recovery.

7. You should see the installed recovery working.

Set up internal storage so the recovery works properly

Warning: This operation WILL DELETE EVERYTHING ON YOUR INTERNAL STORAGE. COPY YOUR FILES ELSEWHERE.

Use your installed recovery to wipe the internal storage, so it becomes available for usage.

Select the option Wipe, then Format data, and then confirm the operation.

No you should be able to use your recovery for other operations.

Make a backup of your current stock ROM

Use your installed recovery to make a backup of your current stock ROM.

Select the option Backup, and then select all partitions, then confirm the backup operation.

After this, don't forget to copy the backup in your computer. For that, you can plug your phone to PC while you are in recovery, and then you can just copy the backup. The backup is stored in the folder named TWRP.

Install a custom ROM

You can use your recovery to install a custom ROM.

The general steps for installing a custom ROM are:

1. Wipe the partitions Data, Dalvik/Cache, System

2. Download the ROM that is a zip file and store the zip file in phone(either internal memory or SD CARD)

3. Use the install option in recovery to install the ROM

4. Reboot the phone.

Install a custom TREBLE ROM

Treble ROMS are different than regular custom ROMS, because they need the phone to have an additional Vendor partition.

To create a Vendor partition, use your recovery to install the zip Exynos7870_CreateVendor_2.0.zip(download from here https://xdaforums.com/galaxy-j7-2017/development/treble-project-treblue-j710x-t4098875) and reboot your phone in to recovery so the recovery detects the new vendor partition.

Then you need to flash a particular vendor(Either Project Treblue, or H-VENDOR).

After that, you can wipe the partitions(Data, Dalvik/Cache, System) and flash the custom TREBLE ROM.

I recommend to flash this custom TREBLE ROM: crDROID https://xdaforums.com/galaxy-j7-2017/development/unofficial-crdroid-6-7-t4119505

To flash crDROID, first install the zip Exynos7870_CreateVendor_2.0.zip, reboot your phone in to recovery, and then flash crDROID(note that the vendor is included in crDROID).

Revert to stock ROM

You can use Odin tool to flash the stock rom. First find your stock rom on https://www.sammobile.com/, unpack the downloaded ROM, and then use Odin tool to flash all the files(BL,AP,CP, CSC)

To revert to stock ROM using your recovery, first install the zip Exynos7870_RevertVendor_2.0.zip(link here https://xdaforums.com/galaxy-j7-2017/development/treble-project-treblue-j710x-t4098875), reboot your phone in to recovery so the recovery detects that the vendor partition is gone, and then restore your previously created backup.