Features, Performance and Recommended Settings
The main feature of CCleaner is to clean and optimize the system by removing unused and temporary files in Windows including the Registry in Windows.
One of the neat features of CCleaner is the ability to create and restore a backup prior optimizing the Windows Registry but users should take caution before using any Registry Cleaners because Windows Registry is the heart of Windows. Any wrong deletion of registry entries can cause system instability or program issues. CCleaner can also clean-up temporary and unneeded files by third party applications. However, if a user would like to keep the generated log files by particular applications, the said files will be removed unless an exemption is added in the Exclusion function in CCleaner.
The most important feature in CCleaner is the option to securely delete the files using different method and one of the welcome additions in CCleaner’s features was provided earlier this year is the ability to wipe the free disk space in the hard-drive. Such feature is often found in commercial tools only! I noticed there is Comodo System Cleaner but when I check the latest version of Comodo System Cleaner, it does not have ability to wipe the free disk space.
When I clean-up the test system that has not been clean for one week, CCleaner left some other temporary files because the default settings is to leave new temporary files. This is why I would like to recommend to users to configure CCleaner using the following settings:
In CCleaner Settings, change the Secure Deletion settings from “Normal File Deletion (faster)" to “Secure File Deletion (slower)" and then choose “NSA (7 passes)"
In Advanced settings of CCleaner, uncheck the boxes before “Only delete files in Windows Temp folders older than 48 hours". You might also want to consider choosing the “Save all settings to INI file" so that the settings is stored as ccleaner.ini in the program directory which you can copy to another PC or if you plan to have a backup copy of the CCleaner settings. Note that if “Save all settings to INI file" is not selected, the setting of CCleaner is still stored via Windows Registry (instead of a file in its directory). Also note that choosing to save the settings to INI file means CCleaner is now portable. If you have pen or any removable drive, you can copy the entire directory of CCleaner in the USB or pen drive and enjoy a portable version of CCleaner whenever you are on the go or helping a family or friend to clean-up their system drive.
When you first install CCleaner, the program automatically configure to wipe the free disk space of the system drive (Drive C). If you have more than one hard-drive or partition, you should allow CCleaner to wipe also the free disk space of the non-system drives.