During the Hard Drive Installation process, it is possible to loosen or disconnect a bundle of internal cables that are responsible for communicating all cameras' video signals to the DVR screen.

If some or all of your cameras do not show on the DVR screen, please check the following:

1. Unplug your DVR from power and remove the top cover of the DVR.

2. Check the cable bundle in the image below.  If this cable bundle is loose or disconnected from the main circuit panel in the DVR, reconnect this cable.

3. Replace the top cover of the DVR and power the DVR back on.