My CanoScan N1220U works flawlessly on my iMac Rev.A and TiBook. Both systems are running Mac OS 9.1 and running on a AC-powered USB Hub. You may want to download the driver from the site and install it again. Hope this help
Kenneth
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Performa 6116CD (60MHz, 72MB RAM, 700MB, A/V)
iMac Rev.A (233MHz, 256MB RAM, 50GB HD,TV/SCSI)
iBook Rev.A (300MHz, 288MB RAM, 3.2GB HD, 12.1)
PowerBookG4 (400MHz, 384MB RAM, 10GB HD, 15.2, Titanium)
Coming Up NeXT: 1GHz G4'Ver (SoLo Video System)
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