Some files just refuse to be deleted. You can clean your computer several times, but when you analyze, the same file is still present. This is usually because the file is locked by an application that is using it.
If this happens, try shutting down the application and cleaning again.
If the file still refuses to be cleaned, then we do not recommend deleting the file manually. If it really bothers you, you can just add the offending file to your exclude list so the file will no longer appear in your analysis results. You can do this by right clicking the file in the results and selecting Add to Exclude list.