fail to find network host

[Homer]

I have a nvr with 8 cameras. everything is hard wired to record. It will lose a camera and say "failed to find network host". I have to unplug the recorder to fix the problem. Reboot does not fix it. It is not always the same camera and is getting worse. I am not hooked up to the internet or a router. I am not trying to view it remotely. I had the system for about a year before I took it out of the box and installed it. I have had it running for a couple of months. Could an outside wifi system be trying to connect or interfere? If so how do I disable remote access or set up a firewall? Thank you

[Revo2Maxx]

Network cable or power issue. Nvr don't have wifi so if not connected to outside line/router then no one is trying to access. My cameras say this on NVR when camera reboots.

First thing I would do is change password on NVR admin account, when prompted to also do cameras click ok. This will insure no one from outside can gain access to camera.

[Homer]

Thank you.

[check6]

In each camera's TCP/IP setting, set the default Ethernet Card to "Wire" and Mode to "Static".

[Homer]

I reset the camera passwords globally. One camera reset failed twice so I had to manually reset it. I haven't had any issues since. Thank you!