Your DVR / NVR system menus are controlled using a USB wired mouse. If you plug in a USB mouse and it is not responding, it may be related to a malfunction in the mouse itself or a need to reconnect your mouse with your system.
LIMITATION: Wireless mice are not supported. Wireless mice require special drivers or software to be installed in order to function. Current DVR / NVR systems do not support the required drivers and software.
To troubleshoot your mouse not responding: