Thanks so much! I really like the way people help each other on the Arduino forum. I've learned so much - but after more than 10 years, I'm still a newbie.
Yes, I'm using 1.8.5 because after I installed 2.x, I found could no longer use the portable features.
I do have 2.x installed on one machine, so I can try using that to replicate the error.
Thank-you - and Happy New Year!!!