I looked at the Hawking and can't see where it could display such a message. Are you sure you didn't mean that this message is on the PC?
I ask because there is so little information about a PC in your post. In fact, no PC is mentioned.
I have Hawking HWR54G router that displayes message "network cable is unplugged". I though that problem appeared because of my modem because router is relativeley new, however problem with router and not with modem. Is there something i should do in setting to fix that or something else. So far i update my firmware and router was working good but only for one day. Problem is back what should i do ?