Network cable

Wait a minute and I will check. ........... a minute passes. No, all of my network cables are plugged. ........... a small, very small, attempt at humor on my part.
" A network cable is uplugged " is a message that you will get when the computer can not make physical connection to any devices.

This could be caused by the cable being disconnected at either end.
The cable is bad.
The computer NIC is bad.
The device on the other end is bad.
Wrong type of cable is connected. ( cross over as opposed to a standard cable ).

These are some examples of what will cause this message to appear.

OK, I am content that I did not answer your question to your satisfaction. Now I have a question for you. What IS your question? "a network cable is unplugged" is a statement and not a question unless you are asking someone if a network cable is unplugged.

Does your computer have both wired and wireless and are you using wireless to access the internet? If so, you probably do not have an ethernet cable connected to the wired port on your computer and that is why you see this.