diff --git a/GongSolutions.Wpf.DragDrop/Utilities/VisualTreeExtensions.cs b/GongSolutions.Wpf.DragDrop/Utilities/VisualTreeExtensions.cs
index 5bd29b13..8e25a068 100644
--- a/GongSolutions.Wpf.DragDrop/Utilities/VisualTreeExtensions.cs
+++ b/GongSolutions.Wpf.DragDrop/Utilities/VisualTreeExtensions.cs
@@ -49,7 +49,7 @@ public static DependencyObject GetVisualAncestor(this DependencyObject d, Type t
     {
       var item = VisualTreeHelper.GetParent(d.FindVisualTreeRoot());
 
-      while (item != null) {
+      while (item != null && type != null) {
         if (item.GetType() == type || item.GetType().IsSubclassOf(type)) {
           return item;
         }
@@ -104,4 +104,4 @@ public static IEnumerable<T> GetVisualDescendents<T>(this DependencyObject d) wh
       yield break;
     }
   }
-}
\ No newline at end of file
+}