All I can tell you is to deal directly with it's maker. Today's answer is "64-bit OS not currently supported" at http://www.nuance.com/naturallyspeaking/products/preferred.asp
Today, now, there is NO SOLUTION. Please don't waste another minute on this until the link above offers support for Vista 64
Bob
I am running Vista on a 64 bit system PC. I get the error message that their version of Visual C++ won't work on a 64 bit system.
I am having a difficult time getting any solutions.

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