The Terminal command seemed to "take", but no joy. Here is the result of my effort:
"softwareupdate[1482]: Triggering background check with forced scan (critical and config-data updates only) ...
KALLT, many thanks for hanging in there with me; 'tis greatly appreciated!
My OS is 10.12.2 and my machine is a 27" i7 iMac, mid 2010.
[doublepost=1484761649][/doublepost]Seems like I bothered you needlessly. Perhaps a case of just not being patient. Still, me thinks your influence played a role.
At any rate, XProtect just auto updated and all is again right with the world.