This error occurs if there isn't any database created on the DVR or if the Database got corrupted.
Fix1: Please log into DVR Settings, then go to”DISK TOOL”, create volumes on the HDD. (Please use 5 volumes less than maximum).
Fix2: If your DVR was working and this error occurs, please go to the DVR Folder and open DBTOOL, this is where your database information is kept. Please ensure all drive state is Ok and all field matches.