CCleaner is able to run automatically and perform scan without user intervention. Here is how:

Open Start Menu > Programs > Accessories > System Tools > Scheduled Tasks. Double-click “Add Scheduled Task” to open the Wizard.

The Scheduler dialog opens and gives you choice of applications from those installed on your PC or laptop. If you don't see CCleaner, go to http://www.piriform.com/ccleaner/download and install it.

ou’ll next choose the day and time when to run the program. For a disk-cleanup tool such as this, running daily or weekly should be just fine. I’m scheduling CCleaner to run at 6:17 PM every day.

At the next screen choose the day and time when to run CCleaner. Running daily or weekly is preferred.

Next, name and provide the password for the Windows user account which will run the program.

At the next step, select the checkbox to open the task’s advanced properties.

No we’ll need to add some command-line arguments, or “switches”, to the Run line to get CCleaner doing scan.

For CCleaner, adding “/AUTO” to the Run line will have the program perform a disk cleanup silently and in the background, then close when done.

Back to the task properties you can see this /AUTO switch present:

Hit OK and you have CCleaner running on the schedule specified!