[hpsdr] Windows 8.1 USB driver - Help!

[Hans J Smit]

Trying to install OpenHPSDR mRX PS v3.4.9 on Windows 8.1 - HP "All in 
one" 64 bit machine, for a friend.
HPSDR Hardware interface is Ozy.
The program is located in: C:/ProgramFiles(X86)/OpenHPSDR/PowerSDR mRX PS/
LibUSB0 Driver for Ozy is located in: 
C:/ProgramFiles(X86)/OpenHPSDR/LibUSB0 Driver for Ozy/
On invoking the program error msg is: "Error starting HPSDR hardware, is 
it connected and powered?"
I have attempted to manually update the driver by going to Device 
Manager, browsing and pointing to the folder, to no avail.
Am I missing something?
Would appreciate any help...    73 Hans VK5YX