OneClickFirewall allows you to block and unblock any application directly from the Windows Explorer or File Explorer context menu.
It does require installation that only takes a minute or two but leaves no trace in programs so to remove it you will need to go to your control panel.
Once installed you can just open Windows Explorer or File Explorer, go to the executable you want to block, right-click on it and select "Block Internet Access." If you want to restore an applications internet access simply repeat the process and select "Restore Internet Access."
User Account Control will pop up when you block access but not when you restore access. It lacks any way of indicating whether an application is blocked or not and there isn't any interactivity or dialogue to let you know that an app is blocked. That said,
OneClickFirewall was not designed to be a full blown application with a GUI but rather a simple way to block internet access to applications with a single click. It is small, free and set-it-and-forget-it until you need it. OneClickFirewall is the perfect application to prevent access to the internet per application.