diff --git a/france/france_rsvp/web.py b/france/france_rsvp/web.py
index 99d69a1..c6d892f 100644
--- a/france/france_rsvp/web.py
+++ b/france/france_rsvp/web.py
@@ -18,7 +18,13 @@ def form():
             'code' in request.form
             and len(request.form['code']) == 4
         ):
-            return redirect(url_for('rsvp', code=request.form['code']))
+            code = request.form['code']
+            try:
+                get_name_and_replies(code)
+            except ValueError:
+                error = "Code invalide"
+            else:
+                return redirect(url_for('rsvp', code=code))
         else:
             error = "Code invalide"
     return render_template('form.html', error=error)