If you get the error message that says "A network cable is unplugged", it normally means that an an installed Ethernet network adapter fails to make a local network connection. Here is how to resolve this issue.
1. Shut down the computer then restart it. You may consider removing the battery after you turn off your laptop, then reattach it and start your device again.
2. Double-click "A network cable is unplugged" error window then click Disable.
3. Check if both ends of the Ethernet cable are not loose. Common IP addresses are 192.168.0.1, 10.0.0.1. Try plugging the cable into a different computer to see if the problem still persists. If yes, you should buy a new cable.
4. Update the network adapter driver software to a newer version