Problem with USB-powered scanner

No, not me... my brother.

He's got a custom-built small form factor PC based on the AMD Athlon 64
3800+, and he's having problems with his CanoScan N670U USB-powered
scanner under Windows Vista Home Premium.

Prior to plugging in the scanner, he downloaded and installed the latest
Vista drivers for the device. All seemed to go well, and he was able to
verify that Vista could recognize the scanner (Control Panel > Hardware
and Sound > Scanners and Cameras; the scanner appeared in the resulting
listing along with his Logitech web cam).

But then he tried to do some scans with Windows Photo Gallery, he ran
into problems. When he chose File > Import from Camera or Scanner..., the
resulting window was blank -- his scanner was not on the list at all.
Confused, he went back to the Scanners and Cameras control panel, and the
scanner was indeed listed there. It just seemed missing under Photo
Gallery.

He tried unplugging and reconnecting the scanner, with no luck.

How could Vista recognize the scanner, but not Windows Photo Gallery? And
how can he fix the problem so that it will work under Photo Gallery?

TIA.

--
Glenn Shaw • Indianapolis, IN USA
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