Let me guess - you have a wireless keyboard and mouse setup?

Connect a wired mouse and go through the control panel to the device manager - expand the HID's and disable them one by one trying to connect to the pronto each time and you should come across the HID causing the conflict - worked for me all be it in Vista 32bit

Each time I need to download I have to disable the wireless set up and use the wired mouse - pain in the ar** but it works

PS don't bother contacting Philips support as I've tried that too many times