About CCleaners rules
When you start CCleaner, you'll see two tabs (Windows and Applications) in the main window, each with several check boxes. These check boxes control many aspects of your system that CCleaner will clean.
To tell CCleaner to clean a particular area of your system, select the check box.
The remainder of this section explains what the check boxes do.
Note: Depending on what programs you have installed on your Windows PC, certain sections and check boxes on the Applications tab may not be available.
To change CCleaner's other settings, see this section.