video not showing

I have a sansa fuze with a blue case.  After plugging the fuze into my pc I look into my video folder and see the you tube video that I downloaded and it plays fine but when I unplug the fuze from the pc and look into my video folder it says empty.  Does anyone have an answer why it does not show.   all my mp3 files are fine.  tks   victor

What is the extension of the video file? Downloaded Youtube files usually have .FLV. Fuze+ can’t play these (only .MP4 ).

Requirements for video files can be found here:

Usually the file must be run through a conversion program. The only free one I know of comes bundled with unwanted (possibly obnoxious) software, so I won’t recommend it.

I used to use SMC which converted flv files with no problem and displayed it full screen on the player.  For some reason smc seemed to stop converting and then I found video4fuze software. That converted flv into mp4 but displayed only three quarters onto my fuze display.  So the question is.  Is SMC still available in a stable form or are there other methods for getting a full screen video.  Tks