Driver for Canoscan N640P for windows vista home premium 64 bits

You may be out of luck; here is a version for XP/NT that you could try to force-feed to see if it will work;

# Model: CanoScan N340P
# Size: 3.73 Mb
# Version: 3.8.2
# Date added: 09-Jan-2007, 10:36
# Manufacturer: Canon
# Device type: Scanner
# Operation system: Windows 98/ME/2000/XP
# MD5: 582d83ae6df3ea4bd0a3465a2750c020

http://www.nodevice.com/driver/CanoScan_N340P/get36948.html

You can download the driver from this IP address (72.56.181.99) within 24 hours. After 24 hours you will have to use the driver request form once again. Thank you for understanding.