Being a software developer I can sometimes get irate with how some software operates. For example, when you uninstall a plugin from WordPress there is no proper cleanup; meaning there are crumbs from the plugin left all over your database. Sometimes it’ll be in your wp_options table and other times little nuggets will be left in the wp_usermeta table. Seriously? I don’t know if it’s the developers of these Plugins or if it’s an inherent flaw with WordPress; either way it completely sucks and can mislead people into thinking they have “completely” removed a specific plugin.
I’ve encountered this problem several times before, but currently I am facing it with the Membership Plugin (http://premium.wpmudev.org/project/wordpress-membership-lite). My user data had become corrupted so I was unable to add any new levels, subscriptions or members to my customers site. Recognizing that something went wrong I utilized their “database” repair functionality to try and fix the issue. It didn’t work, no problem! I’ll just deactivate the plugin, remove it and then reinstall it. Off I go to do just that; but amazingly it remembered every setting that was there before, including the issue that was plaguing me from the beginning. Gah! Darn crumbs. I scrambled through the database to delete all the “leftovers” and sure enough when I removed the plugin and re-installed this time everything worked like a champ!
Please, WordPress or Plugin Developers, consider properly cleaning up after yourselves. My children do a better job after they goto the bathroom!