Bob,
Your question started a search to the preferences. Changed Arduino IDE location and everything is functioning now...I think.
At the bottom of the IDE sketch page there is a green strip. On it text says " Ln1, Col1 Arduino NANO on COM6 ". I still get "Unknown board" when tools looks for board info. Right now, I'm going to ignore the above unless you think I should fuss with it somemore. Please advise when you get a minute. Thanks,
Jon S