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Since you have a 64bit system and Yamaha doesn't have a
driver for it, one of the things you can try.
Go to device manager>click on the device>properties>details tab>drop down menu>hardware id.
Copy and paste the hardware id string into your browser and search fo a compatible driver that way.
Or post a snip of it on here and we can look.
You can also search the Microsoft catalog for one, but I'm thinking your going to have trouble with this one.
Fabe