The system cannot find the path specified?

hey all! I’m new to this so please forgive me if this is a dumb question? All of a sudden I cannot download any new torrents as it tells me the system cannot find the path specified? I can resume previous tasks but cannot begin new ones? Instead of the little green spot to the left of the task it has a red x. The destination I save to shows only empty folders! I am confused so can anyone help?

Is this one problem, or three?

OS?

Client version?

Destination folder?