Can't load new version: Can't find dopuslib

I was trying to load the latest version 12.20 and got a message that it could not find dopuslib
How can I load the latest version?

The most likely reason is antivirus deleting the new DLL because it doesn't recognise it yet. Although for one person, using the alternative, old-style installer (intended for XP users, but works on anything) also worked without having to change any antivirus settings: