[GTALUG] Network disabled on PC after last update

[sciguy]

I have a desktop computer that dual boots into Ubuntu Studio and Windows 
10. It is connected to the internet using a cat-5 cable to my router.

After the last update and rebooting, it turns out that I no longer have 
ethernet on Linux. This is not true on Windows, as I am writing you this 
email from the same computer.

I strongly suspect that there is an update issue that is disabling 
ethernet on Linux. Right now, my computer is in splendid isolation from 
the rest of the world. I can't even see computer resources from other 
computers in my apartment. I also can't see the router itself through my 
browser.

Any ideas as to what to do next to diagnose the problem?

Paul