Download Advanced Registry Tracer
ART, the acronym of Advanced Registry Tracer, is a powerful tool that not only acts as a cleaner of the registry. This part of the operating system can easily get damaged and clogged by a large number of invalid entries, either damaged by you or left behind by uninstalled programs.
ART does more than providing solutions for these problems, it also allows you to prevent further problems. You can create periodic "snapshots" of the registry and browse them like you would normally browse the registry. If something goes wrong you can always load a snapshot as the main registry, as these files also work as back-ups