Vista - Can't get Vhdmount to work on Vista Ultimate SP1

Vhdmount is a small command line application that allows mounting a vhd as
though it were a drive, for file browsing. It uses vhdstor.sys as a driver,
and according to some of the ten or twenty articles I've read, it often
needs to be updated before it will function.

Well, I have updated it mucho times, uninstalled and re-installed till I'm
blue in the face, and it will not work. The driver is dated 8-10-08 and I'm
pretty sure it's the latest available. The error listed in device manager
is "This device cannot start. (Code 10)." I have not been able to find any
useful info about this on the web or on MSFTs site.

The only info that seems relevant is a line at the end of an install
sequence in the devSetupapi.log file. It says, "This device has a PnP
problem."

This seems a bit cryptic. Does anyone have any ideas as to cause and fix?

Thanks,
Mike