devtest unable to load helper device driver

Archived from groups: microsoft.public.windowsxp.device_driver.dev (More info?)

I get this message when trying to run the Device Simulator tool supplied
with the CD for Walter Oney's book "Programming the Microsoft Windows Driver
Model". I have looked in the index and do not find any reference to it. I
also tend to try to run things before I read the book thoroughly, is it
mentioned in there ?

I am using Windows XP, with SP2 recently installed.

Can anyone help ?

thanks !