Grimrock

When ever i try to launch on steam it says "legend of grimrock not available at this time" so I go to game properties and verify game cache and then launch again, it works for a few seconds and then a warning from norton comes up saying grimrock is a security risk. is any one else having this problem ? and is there a way to fix it ?

Tell Norton to allow the game.

Uninstall Norton (yes, I'm serious). Norton is worse than most other malware, imo. Install more sensible (and lightweight) anti-virus and anti-malware tools if you insist on that sense of security, but please do yourself a favor and stop using the likes of Norton.