Accessing tunes on Midi created drive

I recorded several tunes but MuseScore can't find them on the Toshiba "stick". As far as MuseScore is concerned, there is nothing on the drive. Anthem finds them easily and will produce sheet music but Anthem always adds some notes and doesn't always split the hands properly. I'm aware that MuseScore will not deal with Iphone Memo recordings but why not the Midi produced ones.
But, with this memo, I can access the drive. Now totally confused.