@Lee @Carlos Furtado : The suggestions you both gave are not going to completely solve the problem because there is another actual bug in exaile which can result in the mentioned error. Exaile 0.3.2 fails to delete songs from the playlist. Try deleting a song and saving the playlist. Now open the playlist and you will find that song again. Now even if you rebuild your library or mount your drives properly before playing songs it will give you the error "resource not found" if in case you actually delete that song from your system. So that error can arise because of an existing bug in Exaile which won't let you delete songs from playlists.
@Lee @Carlos Furtado : The suggestions you both gave are not going to completely solve the problem because there is another actual bug in exaile which can result in the mentioned error. Exaile 0.3.2 fails to delete songs from the playlist. Try deleting a song and saving the playlist. Now open the playlist and you will find that song again. Now even if you rebuild your library or mount your drives properly before playing songs it will give you the error "resource not found" if in case you actually delete that song from your system. So that error can arise because of an existing bug in Exaile which won't let you delete songs from playlists.