I've installed Wavelab Elements on the Valentines Day sale, but ended up not getting it so I uninstalled it.....but it messed up with some of Cubase's plugins like Stereo and Mono Delays, which I use a lot. Since them, I can't launch any of those.
Please take a look at this screenshot: http://i.imgur.com/hH8SanR.png
Seems like Wavelab took over some of the plugins. I've uninstalled/reinstalled everything and no luck.