Windows Calibre Portable to Mac

Hello. I have an old Windows computer with an extensive collection of my books in caliber portable. When I try to export, I receive the message

You are running calibre portable, all calibre data is already in the calibre portable folder. Export/import is unavailable.

I believe the portable version is 4.

Please assist me in getting the caliber portable library onto my Mac running the latest version Mac OS.

Thank you.