Other than cleaning the data like Unholy Joe demonstrated above, then uninstall the game. Before reinstalling the game be sure you’re opting in to A20 then install. This assures that you have zero A19 files. If you really want to be thorough, after uninstalling, remove all folders that are named 7 Days to Die and The Fun Pimps. You’ll find them in your Steam folder as well as App Data ->I think Roaming or it could be Low. You can also search your registry and delete anything named 7 Days to Die or the Fun Pimps. After that install a fresh copy of A20.
