Run CCleaner and sfc /scannow?

Windows is quite good at correcting errors automatically -You only need to run sfc /scannow if you are aware of a problem or a corruption error appears. You shouldn't need to use it on a regular basis

You can use CCleaner as little or as often as you want - with modern CPUs and large hard drives it doesn't have a huge effect if the computer is running normally. If there is a registry problem then use it but otherwise 2-3x year if at all.

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