Open the extracted folder and run the MSMDownloadTool.exe as an Administrator.
The tool should automatically detect the firmware files within its directory. Connect in EDL Mode: Power off your Oppo A3S. oppo a3s flash file
You should consider flashing the Oppo A3s firmware if you encounter: Open the extracted folder and run the MSMDownloadTool
If a custom ROM installation went wrong and your phone is "bricked" (unresponsive), the flash file can bring it back to life. oppo a3s flash file
Download and install the Qualcomm HS-USB QDLoader 9008 drivers on your PC.
Since a "flash file" is a tool rather than a consumer product, this review is structured as a for technicians and users looking to repair their devices.