K8055n kit not found in PC

Hi,
I 've been using several kits now and the last one I try to use doesn’t react at all. If I use the PIC from a working board the kit works as expected. When I place the suspicious pic in an known good board there is no reaction at all (only power LED is lit) the device is not listed in the pc’s hardware list ( with a working board it does appear correctly).
If I’m correct ( as a service technician) the programed PIC is not functional.
Please advice.
Regards, Dirk

Please return assumed defective PIC for inspection/exchange to:

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