Check your NVR or camera’s storage status to ensure the hard drive (HDD) or SD card is functioning correctly and has enough space.
The error can occur if you try to play back a stream type that isn't being recorded (e.g., trying to play "Sub Stream" when only "Main Stream" is active).
: Completely close SmartPSS. Open Task Manager (Ctrl + Alt + Delete), find any remaining SmartPSS processes, right-click, and select End Task before restarting the program.