Internecine conflict seems to be a recurring theme at Microsoft, but this one takes it to new levels. Somehow, somebody forgot to test the latest patched version of Outlook with the latest patched version of Windows. The result is an error message that makes Outlook inoperable.
The official announcement appears on the Microsoft 365 support site:
After updating to Version 2005 Build 12827.20268 or higher and starting Outlook you may see the following error prompt:
