I have a new PC and had to install Vectorworks 2020 on my new machine. After installation I had this issue with the Vision Library error popping up and I solved it by uninstalling Vectorworks. I went into my Program Files and deleted manually any folders that remained labeled 'Vision2020'. Then I reinstalled Vectorworks and everything worked fine. I opened and closed the program two times to double check. However, after the installation, VW prompted me to install the newest 'Service Pack' update. I therefore, clicked on the link to install the newest service pack. This installation caused an issue with the Vectorworks 2020 program which I had just installed, making the program un-openable. I then had to uninstall VW a second time, and reinstall it in a separate folder with a different name. I then registered the product over the internet but I then did not check for the new service pack this time. VW 2020 then worked fine again. I believe that the new service pack is causing the issue.