InControl (previously “Never10”) created by Steve Gibson is a utility that allows you to set and freeze the major update & feature version of your Windows install. It maintains the system in its current form but still allows security updates.

Note that InControl will hold your Windows right where it is, even after the current version and feature release has gone out of support. You will see a complaint about the current version of Windows requiring an update. But your system will not be updated while you are InControl.