diff --git a/app/views/dmsf/_query_rows.erb b/app/views/dmsf/_query_rows.erb
index 8398ce98..f1ce70b9 100644
--- a/app/views/dmsf/_query_rows.erb
+++ b/app/views/dmsf/_query_rows.erb
@@ -27,8 +27,9 @@
 <% end %>
 <% query.dmsf_nodes(options).each do |node| %>
   <% system = node.title =~ /^\./ %>
+  <% id = (node.type == 'folder') ? "#{node.id}span" : "#{node.id}item" %>
   <% @idnt ||= 0 %>
-  <tr id="<%= node.id %>span" class="<%= cycle('odd', 'even') %> <%= node.css_classes(query.deleted) %> <%= params[:classes] %> <%= @idnt > 0 ? "idnt idnt-#{@idnt}" : nil %>">
+  <tr id="<%= id %>" class="<%= cycle('odd', 'even') %> <%= node.css_classes(query.deleted) %> <%= params[:classes] %> <%= @idnt > 0 ? "idnt idnt-#{@idnt}" : nil %>">
     <td class="checkbox hide-when-print">
       <%= check_box_tag('ids[]', "#{node.type}-#{node.id}", false, id: nil) unless system %>
     </td>
diff --git a/assets/javascripts/redmine_dmsf.js b/assets/javascripts/redmine_dmsf.js
index 062f3961..a0839d33 100644
--- a/assets/javascripts/redmine_dmsf.js
+++ b/assets/javascripts/redmine_dmsf.js
@@ -129,9 +129,14 @@ function dmsfExpandRows(id, parentRow, url) {
     }
   }).done(function(data) {
       // Hide the expanding icon if there are no children
-      if(data.indexOf(' ' +  m[1] + ' ') < 0){
+      if( m && (data.indexOf(' ' +  m[1] + ' ') < 0)) {
+
         $(parentRow).removeClass('dmsf-expanded');
-        $(parentRow).addClass('dmsf-child');
+
+        if(!$(parentRow).hasClass('dmsf-child')) {
+
+          $(parentRow).addClass('dmsf-child');
+        }
       }
       else {
         // Add child rows