Install problem post download

I'm having trouble installing the latest version (4.00). I download it no problem and go through the set up process where I select English and on the next page leave all the tick boxes checked. When I hit Next on the following screen the install button is live for a moment and then instantly greys out leaving me a blank screen except for an ad at the top: "CCleaner recommends Google Chrome..."I've tried disabling McAfee and it makes no difference. I've been using CCleaner happily for a couple of years on my machine (Windows 7) and never had problems before.

Anyone any ideas?

Try CCleaner - Slim . . . http://www.piriform....ccleaner/builds

same program, no Chrome option.

Also see this topic for install problems:

http://forum.piriform.com/index.php?showtopic=5739