'This file has no audio or video streams'

Hello, I'm using PP 5.5 on Windows 7. I'm trying to import am MP4 file, and I keep getting the 'This file has no audio or video streams.' The file plays just fine (I use VLC player). I have also imported half a dozen other MP4 files just fine as well. This is the first one to give me problems. How do I fix it?

Thanks