When I uninstalled Norton AV (before dowloading Avast) the Norton WMI Update would not go off the Windows/Add-Remove. A tech had installed Add-Remove Master on my computer quite awhile ago, and that would usually work if something would stay on the Add/Remove. But I uninstalled it, thinking I would download the newer version, but found out it was only good for 30 days then they wanted $$. I would still like an answer, if anyone knows which is better. Add-Remove Master or Ad-Remove Pro. Surely someone out there knows!
Try CCleaner for a fool proof registry cleaner.