Calc needs to recover existing files, opens them and then crashes inside 5 secs! What's happening?

I updated LibreOffice and all my Calc files became inaccessible. I click on a file in Explorer and a recovery page comes up. I recover the file, it opens and then crashes and LibreOffice closes with no diagnostics at all. A closely similar thing happens if I access the file through LibreOffice’s opening page.