Deleting Click2Flash/corruption of Flash in 10.7.5

It seems the plugin Click2Flash doesn't remove itself simply by removing it from the Plugins folder. I have a 10.7.5 system that says I need to update my Flash plugin, even though I've installed the latest Flash, and removed Click2Flash. Initially Facebook wouldn't allow me in one user to upload multiple photos at once. Now Youtube videos are failing for the same reason. I'm using the latest Safari for 10.7.5 as well. It works fine in another user. One thing which may be affecting it is that is a MacBook Pro 5,3 that seemed to start misbehaving on the Youtube videos only after the machine shut down due to running out of power by accident.

Any idea what could be corrupted, or if there might be other crumbs of Click2Flash hiding somewhere else in the system?