The simplest way to clean a computer's registry after the expiration of trial software is to run a free registry cleaner such as CCleaner after removing the trial software from the computer. Although users can uninstall a program without cleaning the registry, this habit causes a build up of broken items that clutter the system and slow the computer's processing speed.
The first step is to uninstall the trial software using the Control Panel's "Add/Remove Programs." The user must then download a free registry cleaner such as CCleaner. He or she opens the cleaner and selects the "Registry" icon and then the "Scan" button. The program scans the computer's registry and keeps track of potential issues. Once the scan is complete, the user selects the "Fix Issues" button. The program offers the chance to back up the registry file, and it is a good idea to do so. The program then cleans the registry.
It is also possible to manually clean the registry, but experts advise amateurs to avoid attempting manual changes.