I just encountered this very same issue. I found a very simple way to do this. I tried importing the file into every program I have and finally in Izotope rx3 and got the following error msg:
Decode error: Invalide RIFF header:0x0:0x3
I was looking into rewriting the header of the file in a hex code editor, but then i discovered a much easier fix.
If you import the file into Audacity as “Raw Data” it works like a charm. Then you can just reexport the file.
Bam! Easy fix!