Contour DVR deleted all my recordings by itself. Can they be recovered?

My Contour DVR has deleted 100% of its recordings. This afternoon I turned it on and discovered only the morning news was stored, and it showed 0% storage (had been reading ~ 80%). The filter says "all", devices "all". Recently deleted: 7 (The morning news).  Can these recordings be recovered? If not - how do I prevent this?