Install LineageOS on h850

Basic requirements

Important: Please read through the instructions at least once completely before actually following them to avoid any problems because you missed something!

Make sure your computer has working adb and fastboot. Setup instructions can be found here.
Enable USB debugging on your device.

Unlocking the bootloader

Note: The steps below only need to be run once per device.

Warning: Unlocking the bootloader will erase all data on your device! Before proceeding, ensure the data you would like to retain is backed up to your PC and/or your Google account, or equivalent.

Visit LG’s official unlocking website, where you’ll be asked to login.
Follow the instructions and get your unlock file.
Connect your device to your PC via USB.
On the computer, open a command prompt (on Windows) or terminal (on Linux or macOS) window, and type:
```
adb reboot bootloader
```
You can also boot into fastboot mode via a key combination:
- With the device powered off, hold Volume Up + Power.
Once the device is in fastboot mode, verify your PC finds it by typing:
```
fastboot devices
```
Tip: If you see no permissions fastboot while on Linux or macOS, try running fastboot as root.
Now type the following command to unlock the bootloader:
```
fastboot flash unlock unlock.bin
```
Where unlock.bin is the bootloader unlock file you received in the email.
Wait for the bootloader unlocking process to complete. Once finished, you can check if bootloader is successfully unlocked by typing:
```
fastboot getvar unlocked
```
Verify that the response is unlocked: yes. In that case, you can now install third-party firmware.
Since the device resets completely, you will need to re-enable USB debugging to continue.

Tip: It is highly recommended to have the latest official LG stock package installed on the device, before proceeding with unlock.

Installing a custom recovery using `fastboot`

Download a custom recovery - you can download TWRP. Simply download the latest recovery file, named something like twrp-x.x.x-x-h850.img.
Connect your device to your PC via USB.
On the computer, open a command prompt (on Windows) or terminal (on Linux or macOS) window, and type:
```
adb reboot bootloader
```
You can also boot into fastboot mode via a key combination:
- With the device powered off, hold Volume Up + Power.
Once the device is in fastboot mode, verify your PC finds it by typing:
```
fastboot devices
```
Tip: If you see no permissions fastboot while on Linux or macOS, try running fastboot as root.
Flash recovery onto your device:
```
fastboot flash recovery twrp-x.x.x-x-h850.img
```
Tip: The file may not be named identically to what stands in this command, so adjust accordingly.
Now reboot into recovery to verify the installation:
- With the device powered off, hold Volume Down + Power until the LG logo appears, then release Power for a second and hold it again until the recovery comes up.
　
Alternatively, you can use fastboot to boot directly into the freshly flashed or any other desired recovery:
```
fastboot boot twrp-x.x.x-x-h850.img
```

Installing LineageOS from recovery

Build a LineageOS install package.
- Optionally, download additional application packages such as Google Apps (use the arm64 architecture).
If you aren’t already in recovery, reboot into recovery:
- With the device powered off, hold Volume Down + Power until the LG logo appears, then release Power for a second and hold it again until the recovery comes up.
(Optional, but recommended): Tap the Backup button to create a backup. Make sure the backup is created in the external sdcard or copy it onto your computer as the internal storage will be formatted later in this process.
Go back to return to main menu, then tap Wipe.
Now tap Format Data and continue with the formatting process. This will remove encryption as well as delete all files stored on the internal storage.
Return to the previous menu and tap Advanced Wipe.
Select the Cache and System partitions to be wiped and then Swipe to Wipe.
Sideload the LineageOS .zip package:
- On the device, select “Advanced”, “ADB Sideload”, then swipe to begin sideload.
- On the host machine, sideload the package using: adb sideload filename.zip
(Optional): Install any additional packages using the same method.

Note: If you want Google Apps on your device, you must follow this step before the first boot into Android!
(Optional): Root the device by installing the LineageOS SU Addon (use the arm64 package) or using any other method you prefer.
Once installation has finished, return to the main menu, tap Reboot, and then System.

Get assistance

If you have any questions or get stuck on any of the steps, feel free to ask on our subreddit or in #LineageOS on freenode.