dllNotFoundException-EmguCv-HaarCascading

Hey guys,

I'm tyring to use haar cascading for face detection in emgucv with unity.However,there is some problem with classifier and I also tried HaarCascade function but I saw same error again.

Could you please help to me ? why is this problem occur?

My Code:----------

 private Capture cap;
       Texture2D camera;
     private CascadeClassifier classifier;
     //private HaarCascade haar;
 
     void Start()
     {
         // passing 0 gets zeroth webcam
         cap = new Capture(0);
         classifier = new CascadeClassifier("haarcascade_frontalface_default.xml"); //(raw 185)
 
         // adjust path to find your xml  
                 haar = new HaarCascade("haarcascade_frontalface_default.xml");
          
     }

Error:----------

 DllNotFoundException:cvextern.dll
 Emgu.CV.CascadeClassifier..ctor (System.String fileName)
 EmguCamera2.Start () (at Assets/EmguCamera2.cs:185)