Got a valid license key on the second try, downloaded and installed Word and Excel … but this version has an anomaly.
Installed versions of Word and Excel from Microsoft are 16.78.3, and both show a banner on runtime “Upgrade Required.” Doesn’t stop functionality as far as 30 minutes testing revealed, but disabling automatic updates per this page has no effect on disabling the warning banner.
BTW, you cannot deselect the “automatic updates” app from a custom install. All the extraneous apps (Outlook, OneNote, Teams in my case) could be removed from the installation.
Microsoft fails to mention this on there end-of-support page. 
I know, I know — bought this at a very cheap price, so “deal with it.” Still, I’d like to have been forewarned, and would welcome a solution to minimize this.
Thanks, these are Windows recommendations. There is no Registry in macOS, but there might be other files…. (Puts on pith helmet and bush jacket.)
Another page I found had macOS instructions to follow the Check for Updates Help menu command, but that leads you to the dialogs I pictured above. ALLEGEDLY disabling the automatic updates is supposed to work, but no dice. (I haven’t restarted though, so will try that next.)
What about #2 in the First Query part here.
Also, found this for Office 2016. Might be the same. here.
BINGO! The article for Office 2016 had the info needed, the location of the AutoUpdate app that is causing that warning regardless of auto update settings. I hadn’t gotten so far as searching in “/Library/Application Support/Microsoft/” thank you for finding that.
Moving the file to my personal Downloads folder (same as deleting it) did the trick. Banner be gone.
For others, you may need to invoke administrator rights to do this. You can open the folder in Finder by typing ⇧ ⌘ G and typing the full path. You can also use Terminal to cd to the folder, then rm the file … though in my case I used sudo mv /Library/Application Support/Microsoft/Microsoft_AutoUpdate.app ~/Downloads.
The AutoUpdater appears on Sonoma’s Settings, General, Login Items, I’d disabled it but it reenabled itself somehow. 
“Rm that app,… rm that app with extreme prejudice.”
Bought three licenses - finally got around to using them (I know - my fault - but I didn’t have a mac to install them on when I got the licenses) - and none of them work.
This product key was redeemed by Kh*er@outlook.com on November 11, 2024 (47 days ago)
This product key was redeemed by **e.***69@gmail.com on November 11, 2024 (47 days ago)
This product key was redeemed by cp*ic@gmail.com on March 20, 2024 (284 days ago)
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