E_IO_CANNOT_OPEN message

Installed 4.5 on my win 10 pc; upgrade from 4.0 which wasn't working either.

Installed said it could not open "welcome.epub" so I skipped it. Program is installed but with the follwoing error message

E_IO_CANNOT_OPEN  

Any ideas? Is there ANY support for this software? I haven't been able to get it to work since 2016.