You do realize, of course, that the error you have posted doesn't mention Carbonite. At all.
It
does, however, mention Blizzards own "AchievementUI" addon. You can check the "\Interface\AddOns\" folder for the Blizzard "addons". They're all titled "Blizzard_<addon name>", and there are 28 of them. My guess would be that something is interfering with it, but I don't think it's Carbonite.