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The only way to properly get that device working is to either install the old windows 7 64 bit twain driver for the scanner, and try to force it to work on windows 8.
Or, to use the vuescan program ( its a paid program ) and then install the scanner through that program.
Would you like me to connect to your computer via a screen sharing session and get the scanner working for you using the windows 7 driver?
Dustin S.Senior Technician and Network Switching Systems Operator / Maintainer.