The thing that jumps out at me is you say "new to me", which makes me believe this may have been someone else's lappytop? If so, you may need to restore Windoze to the lappytops original state, update it and then install Sentinel... I say this because I am typing this out on a brandy spankin new Windoze 10 lappytop with latest updates and Sentinel installed and works as fine as a frogs hair.. (Given, as it is Windoze!)