On 14 Jun 2024 I experienced a similar loss of Word 10, with any attempt to open a Word document
already saved on my computer being met with a screen saying 'Updating Microsoft 365 and Office, Please
wait a moment.' After a delay, I receive a screen saying 'The application was unable to start correctly
(0xc0001420)"
I feel the same as you: that the Great God Microsoft may have used its access into users of its software
to poison certain functions, even though they were originally paid for, or free. This smacks of an invol-
untary conversion by Microsoft of purchasers of its purchase-and-use programs to a subscription-based
service. which provides MS an ongoing revenue stream.
I can only hope that future litigation will restore my access to my Word files. At worst, some of them may
have been received, and the recipients might be able to print and return, relatively recent distributions.