Removing all of outpost firewall

Okay so here's the deal. I HAD outpost firewall, removed it by uninstalling it with CCleaner, cleaned the registry with CCleaner and Eusing Registry Cleaning and can't find any of it left on my PC myself. However, when I try to install Comodo firewall I get this

How can I find what's left of outpost and remove it?

 

Did you try using the Search command, set to all files and folders, to look for anything listed as outpost? Just a thought.