no doubt there is a registry setting for this. ALL group policy settings boil down to registry settings. The only catch is that here lately Microsoft is starting to get wise to making sure some of these settings don't work unless you're running an enterprise edition of Windows, though I doubt this is one of them I think that only relates to some Windows Update and Telemetry stuff maybe.
I haven't verified the information here, but one of the top three links from this search look promising:https://duckduckgo.com/?q=disable+corta ... 0+registry
I would check out more than one link to make sure the information is consistent and complete. Note that even after changing the registry, you may want to run "gpupdate /force" from an admin command prompt and then rebooting to make sure the settings are in place before the reboot (yes even without group policy editor, you will have gpupdate available.)
I can also easily tell you how to block an .exe if we need to go that route too (hint: IFEO Modifier in d7x) but I don't think that would be necessary.