How do I make a clean version of Quicken on a computer that once had a version installed

I bought a new version of quicken, rather than an upgrade, to that I could start with fresh data / categories / accounts / naming conventions, etc. I do NOT want to revamp the old data which had become completely unusable. How do I get rid of everything, so that I can start completely from scratch. I've tried the uninstall, but there are still lingering aspects.

Thanks in advance.