This means that for some reason it's cleaning out the projects.ini file which keeps all your projects on your list, as well as any mru (most recently used) files.
To fix this just open your copy of Ccleaner, on the left tabs choose the Programs tab. Scroll down to the Utilities section and you should see the HTML Editor listed there. Uncheck that and that will fix this issue and you will no longer lose your projects list or mrus. (If you don't see the HTML Editor on the list, then you're on an older version and will most likely see it there when you update Ccleaner)
Hope this helps others. CC team has been diligently trying to track this issue down for a couple weeks until it was found by another user that it was tied to Ccleaner. The CC team is still looking to see if there is something that can be done to alter this so it doesn't happen at all, but in case they can't, or until it's found at least we have a fix for it.
Thanks to the team for all their help trying to find this issue, and thanks to SirAGE for tracking it down however accidentally it may have been!
