Samsung SCH-i730

I put 3 mpg files on an SD card and it will not list them in the media player. I search them with file explorer and it sees it but when i click on it, it says open the applications and open it from there. Has enyone encountered this? I bought this thing hoping that it would be pretty good in terms of playing video media being that it has windows media 10. Anyone know how to get that working? I never tried avi files. help anyone? 😳