P8055N-2 problem

Good morning,
I’m using P8055N-2 card on Windows 7 Professional 64 bit system (service pack 1).
When I connect the card to USB port Windows freeze and no command is accepted but demo software run correctly.
What can I do?

Thank’s

The K8055N board or USB cable may be defective.
Please check all the solderings on the board.
Can you test it in other PC?

You can return the K8055N for inspection/repair to your local Velleman dealer or direct to:

Velleman Projects Tech. Dept.
Legen Heirweg 33
9890 Gavere
Belgium