Long story seriously shortened... after short support chat with ESET, and several hours support chatting with 2 microsoft techs, both of whom logged into my win10, my Windows Defender Firewall Service could NOT be started. ESET said this a non-issue in the sense that although ESET worked with windows firewall service enabled, if it wasn't that's ok, you are still protected by ESET. Ok, but... ESET said to contact MS support to start the firewall service. Ok! MS concluded that ESET SS Premium had borked the windows firewall, and we mutually decided to uninstall ESET (I can always reinstall it, or NOT!). MS then did a win10 In-Place Upgrade, and that fixed the windows firewall, but not without some snafu's.
The funny part of the story, MS tech2 closed Edge, and opened Chrome to download a win10 iso, I was watching the screen and she seemed irritated with Edge. Made me chuckle amid the chaos of a windows semi-redo. Started at 200pm finished 930pm. It will be another day or two hopefully before the new snafu's are fixed...