The MiniNova Windows driver likely refers to a device driver for a MiniNova USB interface or a MiniNova MIDI controller, which is a part of a line of hardware products by Novation, specifically related to their Novation MiniNova synthesizer or USB audio/MIDI interfaces.
If you're referring to the Novation MiniNova Synthesizer, the driver would enable communication between the MiniNova hardware and your Windows PC, allowing you to edit sounds, manage patches, and use the synthesizer with your DAW (Digital Audio Workstation) for MIDI control. If you mean a different type of device by "MiniNova," let me know.