diff --git a/wcs/forms/root.py b/wcs/forms/root.py
index a8ded5a3a..b7295b1df 100644
--- a/wcs/forms/root.py
+++ b/wcs/forms/root.py
@@ -1141,7 +1141,7 @@ class FormPage(Directory, FormTemplateMixin):
             return json.dumps({'result': 'error', 'reason': reason})
 
         session = get_session()
-        if not session:
+        if not (session and session.id):
             return result_error('missing session')
 
         page_id = get_request().form.get('page_id')