so what the other 2 post - I agree as well... having said that - you are not (yet) in the world of Access - - you are first in a world of pure vba/text file manipulation to get that thing chopped into 3 files...
now that code can be triggered easily enough from Access - but that type code is typically not at this forum..though Hans, a frequent participant, is quite expert in this area and hopefully will chime in....