K8Village! My hero, man! That did it. No reboots necessary for me.
Here's what was particularly amusing. After reading you recommendation, while waiting for it download I tried Microsoft's Virtual Assistant. It somehow managed, with this as its input: "2018-03 cumulative update for Windows 10 Version 1709 for Windows x64-based
Systems (KB4089848) fails", to point me to a completely different fix for a different product! Oy!
I was then surprised when I saw I could have a human call me. I'm thinking this can't likely be very helpful -think of how much it would cost to provide that sort of support to a successful conclusion for free!- but what did I have to lose?
They called me back in about 20 minutes and after asking about my computer model and doing some checking, the fellow said,"the update failed because Lenovo does not provide Windows 10 drivers." Alrighty. I know that's not likely true. Anyway, that's certainly
a reasonable means of getting folks off the line. :-)
Anyway, I then ran the download as you suggested and it worked perfectly the first time. No further reboots after the first one were required. All was up to date.
Thanks, again, for making this so easy!