I'm trying to help a person install an HP All-In-One Printer/Scanner on their desktop, which is running Windows 7. The HP software worked just fine for his laptop, which is running XP (he can both print and scan using the machine which has XP). He said he downloaded all the necessary and applicable drivers (latest and greatest versions) from hp.com, and while the printer works, the scanner does not. When attempting to scan, the error is something along the lines of "Cannot communicate with scanner." Anyone have similar troubles and might be able to offer some words of wisdom? The...