CCleaner browser problem

Hello!

I updated my CCleaner (version 559) and when I ran it, it (apparently) installed CCleaner browser - and changed all my PDFs to HTMLs on the browser. I don't need the browser, but I don't know how to revert all these files (thousands) back to regular Acrobat.

Any help will be greatly appreciated!

find a PDF document on your PC, right click it, click Open with..., click Choose another app, find your preferred PDF program and tick the box Always use this app