Just hit the realisation of not being able to play purchased .m4a files from itunes on another computers itunes that is not internet connected. And cant convert to MP3 ('protected files cannot be converted') My scenario is that I have purchased the track at home and wish to take it into my workplace, an educational institution where I teach music and singing for them to hear the song. This is not breach of copyright and is an exercise of fair use of rights of a purchased recording. Any thoughts, help?