diff --git a/src/AddIns/Misc/HelpViewer/Source/Controls/SearchPadControl.xaml.cs b/src/AddIns/Misc/HelpViewer/Source/Controls/SearchPadControl.xaml.cs
index 9711bc73f4..a8affef636 100644
--- a/src/AddIns/Misc/HelpViewer/Source/Controls/SearchPadControl.xaml.cs
+++ b/src/AddIns/Misc/HelpViewer/Source/Controls/SearchPadControl.xaml.cs
@@ -34,13 +34,12 @@ namespace MSHelpSystem.Controls
 		void DoSearchClicked(object sender, RoutedEventArgs e)
 		{
 			string term = searchCB.Text;
-			if (string.IsNullOrEmpty(term)) {
-				throw new ArgumentNullException("term");
+			if (!string.IsNullOrEmpty(term)) {
+				searchCB.Text = "";
+				if (searchTerms.IndexOf(term) < 0) searchTerms.Insert(0,term);
+				else searchTerms.Move(searchTerms.IndexOf(term), 0);
+				DisplayHelp.Search(term);
 			}
-			searchCB.Text = "";
-			if (searchTerms.IndexOf(term) < 0) searchTerms.Insert(0,term);
-			else searchTerms.Move(searchTerms.IndexOf(term), 0);
-			DisplayHelp.Search(term);
 		}
 	}
 }
\ No newline at end of file
diff --git a/src/AddIns/Misc/HelpViewer/Source/Core/DisplayHelp.cs b/src/AddIns/Misc/HelpViewer/Source/Core/DisplayHelp.cs
index 2e2618eb49..49be86a114 100644
--- a/src/AddIns/Misc/HelpViewer/Source/Core/DisplayHelp.cs
+++ b/src/AddIns/Misc/HelpViewer/Source/Core/DisplayHelp.cs
@@ -17,53 +17,55 @@ namespace MSHelpSystem.Core
 		{
 		}
 
-		public static void Catalog()
+		public static bool Catalog()
 		{
 			if (!Help3Environment.IsLocalHelp) {
 				MessageBox.Show(StringParser.Parse("${res:AddIns.HelpViewer.OfflineFeatureRequestMsg}"),
 				                StringParser.Parse("${res:AddIns.HelpViewer.MicrosoftHelpViewerTitle}"),
 				                MessageBoxButtons.OK,
 				                MessageBoxIcon.Error);
-				return;
+				return false;
 			}
 			if (Help3Service.ActiveCatalog == null) {
-				throw new ArgumentNullException("Help3Service.ActiveCatalog");
+				return false;
 			}
 			string helpCatalogUrl = string.Format(@"ms-xhelp://?method=page&id=-1&{0}", Help3Service.ActiveCatalog.AsMsXHelpParam);
 			LoggingService.Debug(string.Format("Help 3.0: {0}", helpCatalogUrl));
 			DisplayLocalHelp(helpCatalogUrl);
+			return true;
 		}
 
-		public static void Page(string pageId)
+		public static bool Page(string pageId)
 		{
 			if (string.IsNullOrEmpty(pageId)) {
-				throw new ArgumentNullException("pageId");
+				return false;
 			}
 			if (!Help3Environment.IsLocalHelp) {
 				MessageBox.Show(StringParser.Parse("${res:AddIns.HelpViewer.OfflineFeatureRequestMsg}"),
 				                StringParser.Parse("${res:AddIns.HelpViewer.MicrosoftHelpViewerTitle}"),
 				                MessageBoxButtons.OK,
 				                MessageBoxIcon.Error);
-				return;
+				return false;
 			}
 			if (Help3Service.ActiveCatalog == null) {
-				throw new ArgumentNullException("Help3Service.ActiveCatalog");
+				return false;
 			}
 			string helpPageUrl = string.Format(@"ms-xhelp://?method=page&id={1}&{0}", Help3Service.ActiveCatalog.AsMsXHelpParam, pageId);
 			LoggingService.Debug(string.Format("Help 3.0: {0}", helpPageUrl));
 			DisplayLocalHelp(helpPageUrl);
+			return true;
 		}
 
 		public static bool ContextualHelp(string contextual)
 		{
 			if (string.IsNullOrEmpty(contextual)) {
-				throw new ArgumentNullException("contextual");
+				return false;
 			}
 			if (!Help3Environment.IsLocalHelp) {
 				DisplayHelpOnMSDN(contextual);
 				return true;
 			}
-			if (Help3Service.ActiveCatalog == null) {
+			if (Help3Service.ActiveCatalog == null) {				
 				return false;
 			}
 			string helpContextualUrl = string.Format(@"ms-xhelp://?method=f1&query={1}&{0}", Help3Service.ActiveCatalog.AsMsXHelpParam, contextual);
@@ -72,41 +74,43 @@ namespace MSHelpSystem.Core
 			return true;
 		}
 
-		public static void Search(string searchWords)
+		public static bool Search(string searchWords)
 		{
 			if (string.IsNullOrEmpty(searchWords)) {
-				throw new ArgumentNullException("searchWords");
+				return false;
 			}
 			if (!Help3Environment.IsLocalHelp) {
 				DisplaySearchOnMSDN(searchWords);
-				return;
+				return true;
 			}
 			if (Help3Service.ActiveCatalog == null) {
-				throw new ArgumentNullException("Help3Service.ActiveCatalog");
+				return false;
 			}
 			string helpSearchUrl = string.Format(@"ms-xhelp://?method=search&query={1}&{0}", Help3Service.ActiveCatalog.AsMsXHelpParam, searchWords.Replace(" ", "+"));
 			LoggingService.Debug(string.Format("Help 3.0: {0}", helpSearchUrl));
 			DisplayLocalHelp(helpSearchUrl);
+			return true;
 		}
 
-		public static void Keywords(string keywords)
+		public static bool Keywords(string keywords)
 		{
 			if (string.IsNullOrEmpty(keywords)) {
-				throw new ArgumentNullException("keywords");
+				return false;
 			}
 			if (!Help3Environment.IsLocalHelp) {
 				MessageBox.Show(StringParser.Parse("${res:AddIns.HelpViewer.OfflineFeatureRequestMsg}"),
 				                StringParser.Parse("${res:AddIns.HelpViewer.MicrosoftHelpViewerTitle}"),
 				                MessageBoxButtons.OK,
 				                MessageBoxIcon.Error);
-				return;
+				return false;
 			}
 			if (Help3Service.ActiveCatalog == null) {
-				throw new ArgumentNullException("Help3Service.ActiveCatalog");
+				return false;
 			}
 			string helpKeywordsUrl = string.Format(@"ms-xhelp://?method=keywords&query={1}&{0}", Help3Service.ActiveCatalog.AsMsXHelpParam, keywords.Replace(" ", "+"));
 			LoggingService.Debug(string.Format("Help 3.0: {0}", helpKeywordsUrl));
 			DisplayLocalHelp(helpKeywordsUrl);
+			return true;
 		}