Windows 7 - Thumbnail cache

I modified some files in OS, like:
imageres.dll, explorerframe.dll, pnidui.dll and SndVolSSO.dll
When i use Ccleaner, do i have to uncheck the option " Thumbnail Cache " ?!
Thanks.

Two questions:

Why are you modifying system files?

and

Why are you using registry/system cleaners?? (I know Ccleaner has a good reputation and comes highly recommended, but I on principle advise people to never use those things - they're more trouble than they're worth)

I modified them because i wanted to change some icons.
Is that bad fir the OS ?
Second : i use Ccleaner because there is a lot of "rubbish" after surfing the web, windows explorer, etc.
To be honest, i use Ccleaner for a long time, but never got problems with it.

It's just that I've heard reports (which I have not been able to confirm) that changing system icons and the like can interfere with Windows Update, open portals of attack by virus and malware programs, or cause other problems that are hard to diagnose.

For one, you will automatically lose the SFC /SCANNOW solution of fixing problems, because it will always report improper changes - So how do you tell if the changes it reports are you own, or that made my malware?


As long as you're happy.

Me, I stay away from them, even reputable programs such as Ccleaner...

But to answer your original post:

Try this tutorial Thumbnail Cache - Clear and Reset. You won't need to use CCleaner...

Hello Stereo,

Clearing the thumbnail cache will not affect your modified icons in the system files.