How can I get back into TurboTax. Using 2021 Home and Business. Opening program begins an automatic update which fails (error 1603), then relaunch does not happen.

Attempted to manually install updates from their website, and that shows "superpatch installed", but starting TurboTax after this puts me in the same exact loop.  I also attempted all this as admin, and with firewalls turned off.  What next?