First of all, is this a 6600 or a 6700 -premium-? I would remove the software from your computer and install instead from the link below making sure that you are selecting the correct software. Let me know how it responds after that :
http://h10025.www1.hp.com/ewfrf/wc/softwareCategory?cc=us&lc=en&dlc=en&product=5058338
Also, be sure that the USB is not plugged in while you are doing the uninstallation / reinstallation until you are prompted for it.
-Spencer
