After you upgrade the OS to Mac OS v10.6, scanning cannot be performed (Mac OS X v10.6 / Snow Leopard)
Solution
Applicable models:
CanoScan LiDE 100, CanoScan 5600F, CanoScan LiDE 200, CanoScan LiDE 700F
When upgrading the OS from Mac OS X v10.5.x to Mac OS X v10.6 (Snow Leopard), due to the OS specifications, the scanner driver is deleted.
Download the scanner driver supporting Mac OS X v10.6 and install it.