I did wonder about you security apps and possible conflicts but it seems you have it all in hand now. I did have a look around for uninstalling Hitman but it seems many have the same issue. Try checking the apps folder in the c drive as it might have an uninstaller exe? Failing that you could always find the apps folder and delete the contents. Then go through the registry and manually remove it that way. I've done same with problem apps in the past.