LineageOS and Galaxy J7

Preface

Recently, I found out the old smartphone when I was organizing things
It still can work now, so I thought I could use this one to try something fun
And I find it, LineageOS

LineageOS

LineageOS is a customize ROM for Android
Many old device can run modern systems by LineageOS
The newest LineageOS 17.1 is based on Android 10

Steps

I will record my steps to install LineageOS 17.1 here

The following applies to Samsung Galaxy J7 (2015), SM-J700F (j7elte)
Other devices may be a little different

Prepare

Samsung Galaxy J7 (2015), SM-J700F (j7elte)
Micro SD card, at least 1GB
LineageOS 17.1 File (Put to SD card)
Recovery image
Gapps (ARM -> 10.0 -> nano) (Put to SD card)
Odin
SamFirm
Samsung USB Driver
7-Zip

Update system to Android 6.0.1

This step is very important, the original system is 5.1.1, I tried many times without success
But when I update to Android 6.0.1 first, it works

But there is no Android 6 ROM to download in my country
So download it from other countries, I downloaded from India

Run SamFirm program
Model input SM-J700F
Region input INS
Confirm (Check everything except Manual)
Click Download
Wait for downloading

Unzip it, you will get four files

BL_J700FXXU4BRL2_CL14595124_QB21182969_REV00_user_low_ship.tar.md5
AP_J700FXXU4BRL2_CL14595124_QB21182969_REV00_user_low_ship.tar.md5
CP_J700FXXU4BRG1_CL359600_QB10251637_SIGNED.tar.md5
CSC_ODD_J700FODD4BRK3_CL14595124_QB20821888_REV00_user_low_ship.tar.md5

Before proceeding with the following steps, back up your data and restore the system
After restoring the system, Do NOT log in to Google and other accounts

Open Odin, Select BL, AP, CP, CSC in order to correspond to the above four files
Options just keep the default (Auto Reboot、F. Reset Time)

Turn on Developer options
(Settings -> About device -> Build number(Crazy click on this))
Go to Developer options enable OEM unload and USB debugging
Press Volume (-) + HOME + POWER to enter Download Mode
Press Volume (+) then enter Download Mode
Connect J7 to PC

If it is connected, the Odin Log will show the prompt of Added!!
If not, check for driver
Click Start, after that, the device will reboot, then you will see the system upgrade
Do NOT log in to Google and other accounts

After reboot, turn on Developer options and enable OEM unload and USB debugging again
Press Volume (-) + HOME + POWER to enter Download Mode
Press Volume (+) then enter Download Mode

Recovery Image

Rename lineage-17.1-20200813-recovery-j7elte.img to recovery.img
Right click on it -> 7-Zip -> Add to archive…
Archive format select tar

Open Odin, AP select recovery.tar

Start, the device will reboot, then shut down (or directly remove the battery)
Press Volume (+) + HOME + POWER to enter Recovery Mode
If nothing is wrong, the Recovery Mode at this time is lineage recovery

Install LineageOS

First, format data
Click in order Factory reset -> Format data/factory reset -> Format data
Go back
Then, install LineageOS
Click in order Apply update -> Choose from sdcard1 -> select LineageOS zip file
Last, install Gapps (nano is enough)
Click in order Apply update -> Choose from sdcard1 -> select Gapps zip file
After completion, go back
Click Reboot system now