Replacing website with backup, categories remain the same

I backed up my website before using the plugin feedwordpress. Feedwordpress created hundreds of categories that I don’t need as wp_list_categories is an integral part of my homepage. When restoring to backup, copying the backup folder into “My Web Sites” in IIS, and renaming the version containing the extra categories to backup2, the categories are still there. I logged out, cleared my cache/cookies, and restarted IIS. The categories are still there. I don’t know if categories aren’t contained in that folder and are in a database or something but I need to revert to my backup’s state.