When the time comes when your computer is on the fritz and you are looking for registry cleaning software to fix your computer's errors, there are 3 secrets you need to now in order to find the absolute best registry cleaning software available: 1. You should look for a cleaner that can defragment and optimize your registry. Outside of pure effectiveness with regards to detecting and cleaning errors within your computer's registry, this is the most important feature that you should look for when deciding what cleaning software to use.