Understand the consequences of editing the Registry. The Windows Registry stores information about every process, program, and setting on your computer, so removing the wrong entry can result in your computer failing to work properly.

Know the safest way to clean the Registry. Unfortunately, cleaning the Registry by hand isn't safe, and following the steps in this article may not result in your computer speeding up or resolving corrupted Registry entries due to the limited approach you'll have to take. If you want to clean your Registry in an effective, thorough manner without deleting anything important, use the Registry Cleaner app instead.

Understand the process you'll use to manually clean the Registry. The best way to clean the Registry without using a program is by placing your computer in Safe Mode. This will prevent other programs from interfering with your cleaning, becoming corrupted, or making changes to your computer.

Back up your computer. If you accidentally corrupt your computer's Registry, you may need to restore your operating system from a backup.