After reading this post, you will know how to flash the Stock ROM using the smartphone Flash tool on your windows computer.
Step 1: Download the Android USB driver and install it on your computer, If is it already installed then skip this step.
Step 2: Press and hold the Power button and Turn Off your Android Smartphone. If the battery is removable, then remove it.
Step 3: Now Download the Stock ROM and extract it on your computer. (that you want to Flash on your Android Smartphone)
Step 4: Download and Extract SP Flash Tool / Smart Phone Flash Tool on Your Windows Computer. When Extracting is complete you will be able to see the following files:
Step 5: Now Open the Flash_tool.exe file.
Step 6: After a few seconds SP Flash Tool / Smart Phone Flash Tool is launched, then click on the Download Tab.
Step 7: Now click on the Scatter-loading button which is in the Download Tab.
Step 8: Now, find the Scatter File in the Stock ROM folder and select this.
Step 9: Then Click on the Green Download Button to start the Flashing Process.
Step 10: Now, using a USB cable connect your Smartphone to the Computer. (without battery).
Step 11: Press Volume Down or Volume Up key, after connecting the device to the computer, so that the computer quickly detects your smartphone.
Step 12: When a Green sign will appear. The Flashing Process is complete.
Congratulations, Now your Android Smartphone is successfully running the Stock ROM you have Downloaded.