C# haar cascade can't read xml

Hi, I am having a weird problem and struggling with it now.. using( CvHaarClassifierCascade cascade = CvHaarClassifierCascade.FromFile( @"C:\opencv\2.4.11\opencv\sources\data\haarcascades\haarcascade_frontalface_alt2.xml" ) ) Above is my code. And this is really basic cascade loading function which I could find many places. But this code returns an error: > The node does not represent a user object (unknown type?) I tried other xml files but still getting the same error.. Why did it happen and how do I fix it? Please help!!