I had the same issue. I purchased the download from Amazon. I downloaded it twice (2 times) and tried to install / uninstall at least 5 times. Every time it would go through the Update process and then when it tried to load and present to me the Activation Screen, it would error out.
Finally, I did a uninstall and then install again. Went to program directory where I installed it (for me: F:\Program Files(x86)\TurboTax\Deluxe 2020\32bit ) and from within the 32bit folder, I selected the TurboTax application (file type = Application), and then selected it to "Run as administrator" and the activation screen worked.
