to the list of file types that will open with whatever audio player you choose, by going into Tools/Folder Options/File Types in Windows Explorer. You can get an idea of the various things to do when you click NEW by looking at other file type extensions relating to audio (such as .wav or .mp3) so you can fill in the appropriate boxes correctly and using the browse button to choose the player you want when you get to that particular area of choices via the windows you will get as you fill things in.
Once you get it set up for that new .FILE extension type, that program will automatically open up the next time you click on a .FILE type file.
I have a couple of audio files that are in the file format : FILE When I play them, the dialog box about Open With : and the list of softwares on my pc shows up. Now I can play the files using any media player, but the box where I can tick for Always use the selected program ... is greyed out. So now, I can't include these files in any playlists, I can't convert it to regular formats because most of the music converters don't accept the "FILE" format. Can anyone elaborate on these type of files and help with the conversion ? Thank you in advance.