I was using Mac CD version. My OS is Catalina. I spent 2 hours with tech support on the phone, without resolving the issue, including clearing the cache and a clean installation. A couple of days later, I tried logging in as another user, and launching TurboTax 2020. This was successful, and I was able to complete my tax forms and submit them online. Since TurboTax has had this issue for two tax seasons, I hope it gets resolved soon...
