hitman pro

hi, small niggle i have had over the past 6 months, and only have it when using avast pro, any version. certain programs remain in task manager after i close them. hitman is one of them, it closes but remains in task manager until reboot?
any idea what causes this?

Uninstall Hitman pro, delete it folder, remove the startup entry.
Maybe you can use Revo Uninstaller to remove it and its leftovers.

could there be an conflict between those two?

other programs that runs well with avast is malwarebytes antimalware and superantispyware to mantion afew that does a simler job as hitman pro.

tried that, still the same. I cannot find this happening with any other program, and it only does it with avast pro, not really a problem, just an observation. one i cannot figure out.
thanks again.