I recently uninstalled the Portrait Professional plugin from my PC. Photoshop is still showing that the plugin is installed, but of course it doesn't work when I click on it. I can't find any reference to it in the plugins folder, so I don't have any idea how to remove it. Any advice?
Photoshop will only show that the plugin is installed if the plugin really is installed somewhere in the Plug-Ins folder (the plugins installed are checked at launch time). Go to the Plug-Ins folder and see what remains of that plugin.