It appears to be JVCs own Simon as I have tried a few different extension sites without any success.
Does it give an option in the cam to save as something different?
Found this on JVC site about its software,has he got correct/all software available installed as its own software should really be able to open it :
Will My Software run on Windows 98, ME, Windows NT, Windows 2000 Pro, or XP?
We confirmed the following software and drivers compatibility with Windows 95, 98, and ME.
Picture Navigator
JLIP Video Capture
JLIP Video Producer
JLIP Video Player
Card Navigator
USB Drivers
GV-PT2 Printer driver & Capture
GV-DT1 Printer driver & Capture
Video Navigator
None of the above software will be compatible with Windows NT. At this time there are no drivers available to make these software programs compatible with Windows NT. There is an update available for the Picture Navigator software to work with Windows 2000 and XP at
http://www.jvcservice.com/custrel/download.htm. (When executing the update be sure to have Picture Navigator closed).
The following versions of software and drivers will work with Windows XP.
Picture Navigator 2.1.5.1
JLIP Video Capture 3.1
JLIP Video Producer 2.0
JLIP Video Player 1.0
Card Navigator 1.0
USB Drivers
Video Navigator