Hello, I'm using Windows Vista and it's some months I cannot use CCleaner anymore. One day I installed an update of the software (don't remember what version was) and then it crashes when opening it, so I decided to install an older version of it and then it worked, but now it doesn't work it too and older versions too (I tried versions from 4.16 to 4.11). What can I do? I've uninstalled it lot of times and rebooted, I've also used the Windows disk cleaner but nothing changed. As AV I'm using Microsoft Security Essentials and Chrome as main Browser.
Can you say what error messages,if any, you get when you try to run it, and at what exact point does it crash.
Have you tried the portable build from here? (make sure you uninstall all old builds first)
https://www.piriform.com/ccleaner/builds
Are you able to boot into Windows safe mode and run ccleaner? Does it run then?
Do you have any other software on your machine that is not behaving as it should?
Trying to make a screen of the error I uninstalled the program (to make the last attempt) but I've got the icon of ccleaner blocked on the desktop after uninstalling it and I couldn't delete it so I rebooted, found that the icon desappeared, reinstalled the last version 4.16 and NOT launching it from the final window of the installation process but launching it form the icon on the desktop, it WORKED! It doesn't make much sense but now it goes well, thank you for your help.
Glad to hear you are up and running again