diff --git a/Samples/Built-in-Mask/.vs/Built-in-Mask/v16/.suo b/Samples/Built-in-Mask/.vs/Built-in-Mask/v16/.suo
deleted file mode 100644
index e7b0e4f..0000000
Binary files a/Samples/Built-in-Mask/.vs/Built-in-Mask/v16/.suo and /dev/null differ
diff --git a/Samples/Built-in-Mask/ViewModel/BuiltInMaskViewModel.cs b/Samples/Built-in-Mask/ViewModel/BuiltInMaskViewModel.cs
index e4fb10b..2c5ca64 100644
--- a/Samples/Built-in-Mask/ViewModel/BuiltInMaskViewModel.cs
+++ b/Samples/Built-in-Mask/ViewModel/BuiltInMaskViewModel.cs
@@ -36,7 +36,7 @@ public BuiltInMaskViewModel()
             BuiltInMask.NumberMaskProperty = "-8728";
             BuiltInMask.OctalMaskProperty = "/012";
             BuiltInMask.PositiveNumberMaskProperty = "3721972";
-            BuiltInMask.ProductKeyMaskProperty = "HTY23OPY678GR56R01G564GH";
+            BuiltInMask.ProductKeyMaskProperty = " ";
         }
     }
 }
\ No newline at end of file