Cubase 9 LE AI. Serious problem occurred. No ID

While using Cubase, a message poped up; serious problem occurred. It read; Save under new name and restart Cubase.
I have been doing this.
However, now my audio out does not connect. I reconnect in device manager, but there is still no signal sent to the main output bus. I can see the audio signal move in each track, but nothing on main outs.

Hi and welcome,

Try to click the Deactivate All Mute States button (even though it’s not yellow), please.