To play an MP3 file, follow these steps:
Open the Playlist.
Click the Playlist button if the Playlist is hidden.
Optional: Clear the tracks in the Playlist.
Add the MP3 file to the Playlist.
Click the Add button, and then choose Add files from the list.
Locate and select the MP3 file (which is stored on your system), and then click Open.
The MP3 file is automatically added to your Playlist.
Click the Play button.
For more details, see
How To: Use the Playlist