How to install ASUS Zenfone and ROG Phone firmware

Before you start

• Use the image for your exact model and SKU. The version starts with the SKU: WW (worldwide), CN, JP and so on — it must match the version shown in Settings → System → About phone → Software information.
• Choose a version that is newer than the one on the phone.
• Charge above 50% and back up your data.

Steps

1. Copy the downloaded .zip to the top level of the phone's internal storage — not inside a folder. Don't unzip it.
2. Restart the phone, or wait a minute. A notification “System update file detected” appears.
3. Tap the notification and confirm. The phone checks the file, installs it and restarts.
4. When it has restarted, delete the .zip to free up space.

If no notification appears

• Check that the file name was not changed and that the file sits in the top level of storage.
• Check the SKU and the version again: a package for another SKU, or an older one, is ignored.
• Open Settings → System → System updates and check again, or restart the phone.

If something goes wrong

• “Update failed”: download the file again — it may be incomplete — and make sure there is enough free space (about twice the file size).
• Phone won't start after a failed update: hold Volume Up + Power to open the bootloader, choose Recovery mode and use Wipe cache; as a last resort contact ASUS service.