If you don't have any of these situations, but still getting the same issue, I'd recommend doing a clean installation. This allows QuickBooks to create a new folder to replace broken installation files. Let me guide you on how to do that:
I never did get it to complete more than 99% even after running the clean install tool. But I noticed it added a new icon on the desk top, so I ran that, and it successfully installed. Getting the license number was an additional hassle, said I would get an e-mail with that number, but did not.