This could be due to the Digital Rights Management in the purchased file.
- Make sure the software of the store where the file is purchased is running. The first time you run the file a connection to the Internet might be needed.
- The rights in the file are often managed by Microsoft Windows Media Player. Try to play these files with the Media Player before transferring to the portable player.
- Try using the application from your music service to transfer those tracks
- If the track cannot be transferred please try to download another copy from the provider
Note: When you have a file that was downloaded from another player onto your computer it could be that these files will not play.