This is a Speccy discussion so I really don't want to cause an issue by talking about CCleaner, however, I have just had a hellish couple of days trying to upgrade a Win7Pro laptop to Win10. The laptop hung on reboot and has turned out to be unrecoverable (I'm having to reinstall from a Win10 ISO). The very last thing I did was install CCleaner. I've been using it for years, I did not (and never have) use the registry tool. I just used it for basic cleaning and had Active Monitoring on as this is the suggested workaround for CCleaner starting slowly in Win10. So, yes, I'm jumping to conclusions and yes, I could be wrong but when catastrophe happens I always backtrack to the last thing I did - as above, and the laptop was running fine up to that point. Feel free to move this post to the right thread - I only posted here in response to 'DeliciousSalad's post above. Unless someone restores my confidence I will not be reinstalling either CCleaner or Speccy and I'll be removing the former from the laptop I'm using now.