- Your device must be rooted and ClockworkMod recovery must be installed.
- Before proceeding any further backup all your important data like Emails, Messages, Personal Photos, and Videos.
- Make sure USB Debugging mode is enabled on your Android Device. You can enable USB Debugging by going to Settings > Developer Options.
- The device should be charged up to 70% to avoid any unexpected shutdowns. This is very important, any shutdown during the process can damage your device permanently.
How to Install LineageOS 14.1 Android 7.1.2 Nougat Custom ROM on Huawei P9 Lite
- Download Lineage OS 14.1 Android 7.1.2 Nougat Custom ROM and GAPPS for P9 Lite on your computer.
- Connect your P9 Lite with your computer using USB cable.
- Copy/Paste Android 7.1.2 Custom ROM.zip and Gapps.zip files to your SD Card. Make sure to place files on the root of SD Card and not in any folder.
- Then turn off your device and disconnect the USB Cable.
- Now get into recovery mode. Turn On the phone while pressing and holding Volume Up + Power Button together.
- Then in recovery mode perform a full data wipe by selecting wipe Data/factory reset. Use volume rockers for navigation and power button for option selection.
- Now, go to Advanced Option and clear the cache by selecting wipe cache partition and wipe dalvik cache.
- After performing Step 6 and 7, navigate back to the main recovery mode screen and select install zip from SD card.
- Now choose Android 7.1.2 LineageOS ROM zip file, which you copied to your SD Card, and start the installation process.
- Repeat the same process for installing GAPPS after you are done with Step 9.
- That’s it! Now simply navigate to Recovery Mode Main Screen and select “Reboot System Now”. First boot can take up to five minutes.