In this case, we can use a simple software which can be downloaded from internet free of cost. Just search in Google about 'Any Video Converter' and you will get it for your PC.
Install 'Any Video Converter' and open it. Click on 'Add Video Files'. You can see a browser in which you can select the video files in your computer to convert. Select the file you want to convert and Click Open.
Install 'Any Video Converter' and open it. Click on 'Add Video Files'. You can see a browser in which you can select the video files in your computer to convert. Select the file you want to convert and Click Open.