I'm in IT so this was easy for me to do but this has been my work around until Intuit issues a patch...

I created a Windows 10 virtual machine so I'd have a clean Win10 install to work with.

I installed my original download of Quickbooks 2020 R6 then unchecked auto updates so it wouldn't update.

This allowed me to open my existing company file and perform merchant deposits. Quickbooks did nag about opening a company file formatted for a newer version of Quickbooks, however, it still worked. When I'm done with the merchant deposit I close Quickbooks on the virtual machine then open it on my workstation and carry on as usual. I'm only using the virtual machine to process the merchant deposits.

It's dumb that I have to do this but it beats manually entering the credit card transactions and deposits.

Mark