In order to remove redundant items from the Windows registry you need to install a third party software. Here you have a list of the top free registry cleaners for 2013.
CCleaner is the number-one tool for cleaning your Windows PC. It protects your privacy online and makes your computer faster and more secure.
Wise Registry Cleaner
Wise Registry Cleaner can locate and correct problems in the Windows registry, such as missing references to shared DLLs, unused registration entries for file extensions, and missing referenced application paths.
Advanced SystemCare 6 Free
Advanced SystemCare 6 Free takes a one-click approach to protect, repair, clean, and optimize your PC. It also detects and removes spyware and adware.