Moto X4

LineageOS device page

1. Boot the newest TWRP .img from the Official TWRP Project Site.
   1. IF YOU ARE COMING FROM STOCK AND WANT TO INSTALL CUSTOM ROMS FOR FIRST TIME, INSTALL "Copy Partitions Zip" FROM POST #2
2. In TWRP, click "Wipe", "Format Data", then type "yes" as prompted.
   1. ADB sideload the newest weekly
   2. (Optionally) You can flash the newest TWRP Installer also found at the Official TWRP Project Site if you wish to maintain TWRP, though the pre-installed Lineage Recovery instance will do everything you need it to in most cases. We don't recommend or support the use of the TWRP installer, as it is overwritten on every update (will need to be re-installed every update), and has no addon.d-v2 persistence.
   3. Click "Reboot, then choose "Recovery", this will boot you to either Lineage Recovery or TWRP depending on your choice to install TWRP or not. It is necessary to reboot between ROM flash and GApps/Addon flash due to verity/slot-swap logic.
3. (Optionally) Flash GApps - MindTheGApps arm64 are recommended, OpenGApps are compatible with A/B as of 09102018, but I still only reccoemend and support MindTheGApps.
4. (Optionally) Flash SU - you'll need to turn it on from in developer settings after first boot Lineage OS SU Addon.
   1. Magisk works fine, though is not supported.
5. Reboot

(source)

Updater process ended with ERROR: 7

adb shell
rm /system/etc
ln -s /system/system/etc /system/etc

→ flash ZIP again