diff --git a/src/AddIns/Debugger/Debugger.AddIn/Tooltips/PinDebuggerControl.xaml.cs b/src/AddIns/Debugger/Debugger.AddIn/Tooltips/PinDebuggerControl.xaml.cs
index 6dd6e313d3..6a98d5dcd6 100644
--- a/src/AddIns/Debugger/Debugger.AddIn/Tooltips/PinDebuggerControl.xaml.cs
+++ b/src/AddIns/Debugger/Debugger.AddIn/Tooltips/PinDebuggerControl.xaml.cs
@@ -167,7 +167,7 @@ namespace Debugger.AddIn.Tooltips
 		
 		#endregion
 		
-		#region Expand buton
+		#region Expand button
 		
 		private ToggleButton expandedButton;
 
@@ -185,6 +185,9 @@ namespace Debugger.AddIn.Tooltips
 		
 		void BtnExpander_Checked(object sender, RoutedEventArgs e)
 		{
+			if (!DebuggerService.IsDebuggerStarted)
+				return;
+			
 			var clickedButton = (ToggleButton)e.OriginalSource;
 			var clickedNode = (ITreeNode)clickedButton.DataContext;
 			// use device independent units, because child popup Left/Top are in independent units
@@ -319,12 +322,12 @@ namespace Debugger.AddIn.Tooltips
 		
 		void RefreshContentImage_MouseDown(object sender, MouseButtonEventArgs e)
 		{
-			// refresh content
-			ITreeNode node = ((Image)sender).DataContext as ITreeNode;
-			
 			if (!DebuggerService.IsDebuggerStarted)
 				return;
 			
+			// refresh content
+			ITreeNode node = ((Image)sender).DataContext as ITreeNode;
+			
 			var resultNode = currentDebugger.GetNode(node.FullName, node.ImageName);
 			if (resultNode == null)
 				return;
diff --git a/src/AddIns/Debugger/Debugger.AddIn/TreeModel/ExpressionNode.cs b/src/AddIns/Debugger/Debugger.AddIn/TreeModel/ExpressionNode.cs
index b98e3edd52..85c59bf3ec 100644
--- a/src/AddIns/Debugger/Debugger.AddIn/TreeModel/ExpressionNode.cs
+++ b/src/AddIns/Debugger/Debugger.AddIn/TreeModel/ExpressionNode.cs
@@ -31,7 +31,6 @@ namespace Debugger.AddIn.TreeModel
 		Expression expression;
 		bool canSetText;
 		GetValueException error;
-		string fullName;
 		string fullText;
 		
 		public bool Evaluated {