When I try to install CCleaner I get an error message concerning a file called ytb3.exe I'm not sure if the file can't be found or it's corrupt or something. If anyone could help I'd appreciated very much.
It is the yahoo toolbar which comes bundled with the full version but you can untick this option when installing.
If you just want the slim (no toolbar) option, see here
http://www.CCleaner.com/download/builds
Uninstall other version first.