I have a window frame as a static model, inset_windowframe_large3, that used to have a collision model denying access to a room. Now players can walk right through it. I set the collisions from "Use VPhysics" to "Use Bounding Box" and after recompiling it works like it should. I also have a couple of boats, models/props_canal/boat001a.mdl, with the a similar problem but set as prop_physics_multiplayer - players can walk right through. Thinking is was prop_physics_multiplayer entity setting I changed it to prop_physics and it reacts like it should. I have other prop_physics_multiplayer in the map the work as they should so it doesn't seem to be the initial entity setting. The collision models don't show up at all for the window frame in Hammer, but collision models for the boats do.

Any ideas?

Cheers