Try deleting the current download, of Black Hole 215, from your PC, then download it again:
http://www.vuplus-community.net/board/threads/black-hole-vu-duo2-2-1-5.21515/
Unzip the Black Hole 215 file and extract the vuplus folder to your USB stick. Then try loading the new version, in the usual manner.
Turn off the receiver, at the rear.
Insert the USB stik, in the front USB port.
Turn on the receiver, at the rear, hold in the front power switch, near the front USB port, until the receiver states reading USB.
Once loading has completed remove the USB stick and allow the receiver to boot up.