diff --git a/Espera.View/DragDropExtension.cs b/Espera.View/DragDropExtension.cs
index 8ac6ee6a..6b6050a9 100644
--- a/Espera.View/DragDropExtension.cs
+++ b/Espera.View/DragDropExtension.cs
@@ -86,7 +86,7 @@ private static void HandleScrollOnDragDropChanged(DependencyObject d, Dependency
         {
             FrameworkElement container = d as FrameworkElement;
 
-            if (d == null)
+            if (container == null)
             {
                 Debug.Fail("Invalid type!");
                 return;
@@ -160,4 +160,4 @@ private static void Unsubscribe(FrameworkElement container)
 
         #endregion ScrollOnDragDropProperty
     }
-}
\ No newline at end of file
+}