CCleaner has a bug in its module making it wipe %systemroot%\Installer folder even if cleaning of it isn't selected.
Its PITA to get that folder deleted on Windows 7 x64 Pro, since every darn update for .net, vb, c++ etc. fails!
Can't even install Visual Studio after CCleaner did its crap.
Sorry if I sound a bit mad, but it is a shame that such a nice tool has such bug.
I wonder if no one else hasn't reported this yet...
I have seen the %systemroot%\Installer folder emptied on a computer before and if it does get emptied you will run into many problems. This folder should not be cleaned. Unless you are 100% positive the software has been removed from your computer. I was not aware CCleaner cleaned this folder but if it does and removes software that is still installed you will run into problems.
Seems selecting IIS cleanup on previous versions triggered it, at least I can't replicate it with CC 2.27.1070