diff --git a/PROMS/Volian.Controls.Library/DisplaySearch.cs b/PROMS/Volian.Controls.Library/DisplaySearch.cs
index 11db70da..d17e367d 100644
--- a/PROMS/Volian.Controls.Library/DisplaySearch.cs
+++ b/PROMS/Volian.Controls.Library/DisplaySearch.cs
@@ -388,8 +388,18 @@ namespace Volian.Controls.Library
 			lstCheckedStepTypesStr.Clear();
 			topnode.Text = "Types";
 			advTreeStepTypes.Nodes.Add(topnode);
-
-			FormatData fmtdata = _MyDocVersion.ActiveFormat.PlantFormat.FormatData;
+			FormatData fmtdata = null;
+			// B2017-181: selecting/deselecting, and no nodes are selected was causing null reference when trying
+			//	to access the DocVersion (none are selected), use the format off of the top folder:
+			if (_MyDocVersion == null)
+			{
+				FolderInfo fi = FolderInfo.Get(TopFolderID);
+				fmtdata = fi.ActiveFormat.PlantFormat.FormatData;
+			}
+			else
+			{
+				fmtdata = _MyDocVersion.ActiveFormat.PlantFormat.FormatData;
+			}
 			List<StepDataRetval> lstSrchStpTypes = fmtdata.GetSearchableSteps(); // list of searchable step types
 			if (lstSrchStpTypes != null && lstSrchStpTypes.Count > 0)
 			{
diff --git a/PROMS/Volian.Controls.Library/StepTabRibbon.cs b/PROMS/Volian.Controls.Library/StepTabRibbon.cs
index a57af697..a412f8d5 100644
--- a/PROMS/Volian.Controls.Library/StepTabRibbon.cs
+++ b/PROMS/Volian.Controls.Library/StepTabRibbon.cs
@@ -1587,7 +1587,8 @@ namespace Volian.Controls.Library
 			StepTabPanel tmp = Parent as StepTabPanel;
 			if (tmp.MyDisplayTabControl.MyCopyStep != null)
 			{
-				if (!tmp.MyDisplayTabControl.MyCopyStep.IsEnhancedStep)
+				//B2017-180:  The fix for B2017-158 also needed the 'HasEnhancedLinkedStep' to check if the copied step is a source step
+				if (!tmp.MyDisplayTabControl.MyCopyStep.IsEnhancedStep && !tmp.MyDisplayTabControl.MyCopyStep.HasEnhancedLinkedStep)
 				{
 					if (MyItemInfo.IsEnhancedStep) btnPasteReplace.Enabled = btnCMPasteReplace.Enabled = false;
 				}
@@ -1623,7 +1624,8 @@ namespace Volian.Controls.Library
 			btnPasteBefore.Enabled = btnCMPasteBefore.Enabled = enable;
 			btnPasteAfter.Enabled = btnCMPasteAfter.Enabled = enable;
 			//B20170-158 Don't allow a step to replace a linked step
-			btnPasteReplace.Enabled = btnCMPasteReplace.Enabled = enable && !MyItemInfo.IsEnhancedStep;
+			//B2017-180:  The fix for B2017-158 also needed the 'HasEnhancedLinkedStep' to check if the copied step is a source step
+			btnPasteReplace.Enabled = btnCMPasteReplace.Enabled = enable && !MyItemInfo.IsEnhancedStep && !MyItemInfo.HasEnhancedLinkedStep;
 		}
 		private void SetPasteButtonEnabled()
     {