Sorry Mark, tried all that,and still no joy.
I did re-try the previous suggestion.
To the first entry, got, "network is unreachable".
Second entry got a huge mass of numbers and letters, which completely baffled me.
No reply to the third and fourth entries, but it did clear the network center. When I created a new network connection, the summary said that, the Interface,Speed,Driver and Hardware Address were all unknown. Don,t know if this is significant. Thanks for the suggestions. Still no network light showing.