hmm, no actual errors there, just warnings. Check the name of anything in your scene(making sure no objects are named something like a bone that will get created. “head” for example). make sure there aren’t any joints before going into deformation phase. Lastly, if you open this file, relaunch the UI by choosing character rig creator again in the menu, and then try, does it work? I’m wondering if you had the UI left up while working on a new character and it needed to be refreshed.
Also, do you have any namespaces in the scene? Go the window->general editors->namespace editor and make sure only the root namespace is in there. if there is anything else, delete them and choose merge with root as the option.