Hi Mick,
are you executing the action as the usual way? because it seems that the action is not sited. I'm not sure if it's your case, but If you're trying to execute an action from another action, you have to site it before to call the Execute.
something like this:
public void Execute()
{
FooAction fooAction = new FooAction();
this.Container.Add(fooAction);
fooAction.Execute();
}