[Sorry, accidentally hit send as I was writing]
If it's on your motherboard, you could disable
it in the BIOS as well but you'd best consult your
motherboard manual for instructions on that.
....if you do need it, check out the site of
the device manufacturer (mpu-401 is a generic
MIDI driver) the MIDI port might be on your
motherboard or soundcard, for example - and
see if there's updates for it. (Do a "view devices
by connection" 'in Device Manager' to see what
it's attached to.)