SysToSys

I have a Windows computer and recently it is slow. I think it has a lot of junk files and want to clean them all. While checking for junk files, I do not know which are the junk and which are the necessary files. Is there any standard method to delete all unnecessary junk files from a Windows PC?

Avast Junk file remover is a good tool to remove all junk files from your computer.

Thank you Prasad, but I do not wish to install any third party app to do this.