If this is just for downloading photos to the computer, I would strongly suggest just getting a USB card reader instead. It's cheap, faster, and much, much easier. Canon's WIA drivers are notoriously difficult to get to work, while the card readers are as easy as plugging them in.
Comments
Did you buy the camera new? Should have come with one. Canon part #IFC-400PCU. Probably an exact equivalent at any computer store.
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