The LegalSounds services has been closed down. This means your account is no longer valid. Even if the software is still present on your computer, there won't be the possibility to download MP3s from the servers since they've been shut down. You will have to look for another service. Why not try Spotify or Pandora? They're free, and although you can listen an enormous quantity of tracks, you won't have download them since streaming can be achieved on almost all platforms.