Unlike professional Yamaha synthesizers (like the Motif or MODX), the PSR-E403 is a class-compliant USB MIDI device.
The is a piece of legacy software that requires patience to install on modern systems. While Windows users have a fighting chance with the V3.1.4 driver and some troubleshooting, Mac users are largely left in the cold. However, with the hardware workaround (USB host to MIDI converter), your trusty PSR-E403 can continue making music for another decade. yamaha psr e403 midi driver
Windows is trying to use its generic driver. Solution: Unlike professional Yamaha synthesizers (like the Motif or
Apple has deprecated kernel extensions (kexts) that legacy Yamaha drivers rely on. For Mac users, skip to Part 7 for a workaround. yamaha psr e403 midi driver