I honestly don't know why they wouldn't open. Are these m3u files located in your storage or are they URLs?
Try VideoLAN vlc player. dL it, install, and double click on .m3u file. Associate program with file. About the best d@mn media player sw out there. don't use Windows Media Player. It's evil. and so is Bill Gates
Wait for it.. Isn't an m3u file a playlist file??? Seem to remember that it is as I can edit them with a text editor.... unless you have the files (mp3) that it lists there isn't anything to open and play.. The Cardigans - Life.m3u So there it is.. you can load them into a media player, as long as they refer to audio files in the same folder.. but to open them in the traditional sense you need a text editor. mentioned Winamp.. free and a classic. new anniversary edition out now.