I have the same problem with the following Phidget Control panel :
Phidget21 - Version 2.1.8 - Built Oct 28 2011 14:53:00
Phidget21.Net - Version 188.8.131.52
I've installed the Phidget 21 Installer for 64 bit in my windows 7 laptop.
The Phidget I'm trying to detect is the PhidgetRFID 1023 (most likely rev 1)
The installation took a while (about 5 minutes) without any sort of progress and all of a sudden it was finished stating it was installed without error.
Any help is welcome, thanks