Exported Track Has No audio?

Strange thing happened. I went to export a track in Cubase, have been doing this for a long time and never had a problem, but today suddenly whenever I export a track, and then go and listen to it playback, there is no sound and it can’t be played! I have checked everything, the sample rate, the monitor switch etc, and it still any exported tracks, when I open wav. file to listen there is nothing! What has happened??

There is no sound or it can´t be played?