Excel version 16.34 has not fixed this issue

excel-prompts-you-to-grant-access-to-files-and-then-hangs-or-shows-a-warning-that-it-cannot-open-the-xlsx-file-because-the-format-or-extension-is-not-valid

I'm using Mac OS 14.7.2 and Office 365, Excel v 16.92

Having strange issues with 'file open', 'open recent' and Save.   Lots of the slows...

Recently I completely replaced Office 365 but still same troubles.

Any clues?  I've wondered, is it because, upon installation, I've accepted "sending optional data" How can I turn that off once I accepted it? (Would that make a difference, I don't know...)