You should check for updates to CCleaner regularly, so you have the latest version that can do the best job keeping your PC accurate and fast.
To check for updates, click the Check for updates... link at the lower right-hand corner of the CCleaner window.
The Check for updates link in CCleaner.
Your Internet browser will open and the CCleaner site will tell you if you have the latest version, or will give you a link to the latest update.
While you're there, be sure to sign up for news about CCleaner by entering your email address in the form provided.