We cross posted;
I see you tried to put the Library with the program (that was a

Windows 3x,9x method). Windows security has gotten way better and protects program area from changes.
FWIW. Calibre also protects against creating a Library (with the contents) on an occupied folder. The folder used must be empty when creating a New Library (New/Updates to Calibre will detect and allow a proper Calibre Library structure )