I'm receiving the errors below when trying to import the latest version of Ultimate Inventory System. I removed any remenance of it in the project, as well as the Asset Store package. I do not know what else to do.
All the errors are coming from the PlayerInput class - is the sole purpose of this class related to First and Third Person Character controller? I do not use either in my project.
I'm guessing that you had UCC imported and then removed it? You'll also want to remove the compiler definitions associated within it within the Player Settings: