Dwarf

Since the device operates when you use XP, that eliminates hardware problems. It sounds as though your machine originally had XP on it, and you installed Vista on to it without disconnecting your peripherals. Problems like this are typically caused by incorrectly installing software, both the operating system and application software. When installing Vista, or any other operating system, DISCONNECT ALL peripherals apart from your mouse, keyboard, and monitor from your system. Once the operating system has installed, you need to follow the instructions from the peripheral manufacturer as to how to install their device. Some require the drivers to be installed prior to the device being connected to the PC, others have this requirement the other way round. Make sure that you have the latest drivers available for your device for your OS. These can be obtained from the device manufacturer, although sometimes a basic driver is built-in to the OS.
Dwarf