I have the MX850. Sean-78's instructions are fully applicable. The Windows 8.1 drivers will allow you to use the scanner. On a related note: Photoshop does not support TWAIN scanners on 64-bit Windows platforms, so I use the 'MP Navigator MX' software that is also available for download on the Canon support website. The following articles provide information about the bundled scanner driver and software and detailed instructions to install them. What is a scanner driver? What is MP Navigator EX? How to install the driver / software for a USB connection? Click here for Windows Click here for Mac OS X; How to Install the driver / software for a wired LAN.
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