I have just installed CIS 3.8.65951.477 on my daughters laptop & all the computer does now is loops the start-up process (i.e. you switch the computer on, you get the Microsoft Coropration Screen with the green progress bar, the the screen goes black with the mouse pointer on it, then it re-starts.)
Well, I guess the only option is to boot to safe mode and uninstall/reinstall.
When you see the BIOS screen (the screen before the Windows loading screen) continually press F8 and then select Safe Mode and uninstall CIS. Then reboot to normal mode and clean our your registry with something like Reg Seeker or the registry cleaner in CSC. Then try a fresh install.