Repeats one frame throughout entire video

A couple of years ago, I discovered Shotcut and converted an .wmv video to .mov for display on our nonprofit web site. At the time, this video played fine. Today, I noticed the video would play the sound track but only display one video frame throughout the entire video (not the first frame). I checked my offline copy that was originally uploaded and tested, and it did the same thing. I found the original .wmv file and it played normally (offline).

Any ideas what might have happened and how to correct it? When I bring either the .mov or .wmv file into Shotcut now, it shows only one video frame. Obviously, I don’t really know how to use Shotcut, but did manage to convert a video or two back when I first downloaded it.

Thanks

If you are just using Shotcut as a transcoder, try Handbrake instead (also free)