[PLUG] Network troubleshooting help (urgent)

[John Jason Jordan]

I am sitting here with my new Thinkpad P73, and no internet.

Yesterday I had not yet shut down and removed my old computer, so the
Thinkpad was connected directly to the cable. Ethernet worked then, but
wifi did not exist. At the command line ifconfig just showed eth0 (now
called enp0s31f6) and lo (loopback). As long as the cable was working I
decided to leave wifi for later.

Just now I shut down the old computer and put the Thinkpad in its place
on my desk. I carefully plugged everything into the Lenovo Thunderbolt3
dock and then connected the dock to the Thinkpad. Everything is working
except both ethernet and wifi are now dead. At the command line
ifconfig still shows enp0s31f6, but it is not connected. I tried sudo
ifconfig enp0s31f6 up, which executed without error, but still no
connection. I can't ping anything on my network ('network is
unreachable'). As before, wifi still does not exist.

There is a green light where the cable connects to the dock, or at the
computer if I connect it directly. However, the light is solid, not
flashing as it usually does. I also replaced the cable, even though the
green light probably indicates a good connection.

I rebooted and looked all over the BIOS for some setting that might
have turned off wifi, but found nothing. Years ago I had a computer
that wouldn't connect to wifi until I found a physical switch that was
on 'airplane mode.' On this computer there is no such switch, nor can i
find a keyboard button with an airplane on it, or anything else that
looks promising.

I am writing this on my desktop computer. I really need the Thinkpad to
connect!