Graham, I'm attaching a ZIP file that contains the old version 1.2.2 of Yamaha's USB-MIDI driver. It says it's for Windows 98 and Windows ME, but doesn't say it works with Windows 95, so I don't whether it will work or not. There are installation instructions in the readme.txt file in the folder.
Note that whenever you use a MIDI interface to connect from a keyboard's MIDI ports to a computer's USB port, you must use the driver that goes with the MIDI interface, not the driver that goes with the keyboard. For instance, for the M-Audio MIDISPORT you would need to use whatever driver M-Audio made for the MIDISPORT, regardless of whether you're using the MIDISPORT to connect a Yamaha, Casio, Roland, Korg, Moog, Nord, or other keyboard with MIDI ports. M-Audio did make a driver, but they say it isn't needed unless you're trying to use the MIDISPORT with more than one program simultaneously. Also, I don't know if they made a version of the driver that worked with Windows 95.
So to recap, do not try to use the Yamaha driver with the MIDISPORT. If you do want to try using the attached Yamaha driver, just connect the keyboard directly to the computer using a USB cable and the USB TO HOST port.
I just had a thought. Do you know what kind of USB port is on the computer-- i.e., is it USB 1 or USB 2? It's possible that the connection problem is due to using a USB 2 cable when the computer has a USB 1 port. If that's the case, you might need to see if you can find an old USB 1 cable to try.
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