diff --git a/lib/classes/Controller/Setup/Upgrader.class.php b/lib/classes/Controller/Setup/Upgrader.class.php
index 9dc1a2f2fb..a3928baf45 100644
--- a/lib/classes/Controller/Setup/Upgrader.class.php
+++ b/lib/classes/Controller/Setup/Upgrader.class.php
@@ -49,6 +49,7 @@ class Controller_Setup_Upgrader implements ControllerProviderInterface
                   'locale' => Session_Handler::get_locale()
                   , 'upgrade_status' => $upgrade_status
                   , 'available_locales' => $app['available_languages']
+                  , 'bad_users' => User_Adapter::get_wrong_email_users(appbox::get_instance())
                   , 'version_number' => GV_version
                   , 'version_name' => GV_version_name)
               );
diff --git a/lib/classes/Exception/Setup/FixBadEmailAddresses.class.php b/lib/classes/Exception/Setup/FixBadEmailAddresses.class.php
new file mode 100644
index 0000000000..659d857471
--- /dev/null
+++ b/lib/classes/Exception/Setup/FixBadEmailAddresses.class.php
@@ -0,0 +1,21 @@
+<?php
+
+/*
+ * This file is part of Phraseanet
+ *
+ * (c) 2005-2010 Alchemy
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * 
+ * @package     Exception
+ * @license     http://opensource.org/licenses/gpl-3.0 GPLv3
+ * @link        www.phraseanet.com
+ */
+class Exception_Setup_FixBadEmailAddresses extends Exception
+{
+  
+}
\ No newline at end of file
diff --git a/lib/classes/Setup/Upgrade.class.php b/lib/classes/Setup/Upgrade.class.php
index cda2f132fd..e038daae29 100644
--- a/lib/classes/Setup/Upgrade.class.php
+++ b/lib/classes/Setup/Upgrade.class.php
@@ -54,6 +54,12 @@ class Setup_Upgrade
     if (self::lock_exists())
       throw new Exception_Setup_UpgradeAlreadyStarted();
     $this->appbox = $appbox;
+    
+    if(count(User_Adapter::get_wrong_email_users($appbox)) > 0)
+    {
+      throw new Exception_Setup_FixBadEmailAddresses();
+    }
+        
     $this->write_lock();
 
     return $this;
diff --git a/lib/classes/module/console/systemUpgrade.class.php b/lib/classes/module/console/systemUpgrade.class.php
index 48e68b864c..529d15c3c7 100644
--- a/lib/classes/module/console/systemUpgrade.class.php
+++ b/lib/classes/module/console/systemUpgrade.class.php
@@ -59,6 +59,12 @@ class module_console_systemUpgrade extends Command
       {
         $output->write('<info>Upgrading...</info>', true);
         $appbox = appbox::get_instance();
+        
+        if(count(User_Adapter::get_wrong_email_users($appbox)) > 0)
+        {
+          return $output->writeln(sprintf('<error>You have to fix your database before upgrade with the system:mailCheck command </error>'));
+        }
+        
         $upgrader = new Setup_Upgrade($appbox);
         $advices = $appbox->forceUpgrade($upgrader);
       }
diff --git a/templates/web/setup/upgrader.twig b/templates/web/setup/upgrader.twig
index 2d0211e217..d2169475c4 100644
--- a/templates/web/setup/upgrader.twig
+++ b/templates/web/setup/upgrader.twig
@@ -40,7 +40,6 @@
 
   {% endif %}
   $(document).ready(function(){
-    console.log('hello update_button');
     $('.update_button').bind('click', function(){
       $(this).attr('disabled','disbaled');
       $('.upgrade_loader').show();
@@ -70,24 +69,36 @@
               <tr>
                 <td>
                   {% if not upgrade_status.active %}
-                  <p>
-                    {% trans 'Une mise a jour de l\'application est necessaire, il est vivement recommande de l\'effectuer en ligne de commande via la commande :' %}
-                  </p>
-                  <p>
-                    <code>
-                      {{registry.get('GV_cli')}} {% if registry.get('GV_PHP_INI') %} -c {{registry.get('GV_PHP_INI')}}{% endif %} bin/upgrade.php
-                    </code>
-                  </p>
-                  <p>
-                    {% trans 'Si toutefois vous n\'aviez pas acces à la console, suivez le lien suivant' %}
-                  </p>
-                  <p>
-                    <form action="/setup/upgrader/execute/" method="POST" target="update_target">
-                      <button class="update_button">{% trans 'Mise a jour' %}</button>
-                      <img style="display:none;" class="upgrade_loader" src="/skins/icons/loader111111.gif"/>
-                    </form>
-                    <iframe style="display:none;" src="about:blank" name="update_target"></iframe>
-                  </p>
+                    {% if bad_users|length > 0 %}
+                    <p>
+                      {% trans 'Before any upgrade, you have to fix your database.' %}
+                      {% trans 'Some users have the same email address. You can fix this problem with this script :' %}
+                    </p>
+                    <p>
+                      <code style="width:90%">
+                        {{registry.get('GV_cli')}} {% if registry.get('GV_PHP_INI') %} -c {{registry.get('GV_PHP_INI')}}{% endif %} bin/console system:mailCheck
+                      </code>
+                    </p>
+                    {% else %}
+                    <p>
+                      {% trans 'Une mise a jour de l\'application est necessaire, il est vivement recommande de l\'effectuer en ligne de commande via la commande :' %}
+                    </p>
+                    <p>
+                      <code style="width:90%">
+                        {{registry.get('GV_cli')}} {% if registry.get('GV_PHP_INI') %} -c {{registry.get('GV_PHP_INI')}}{% endif %} bin/console system:upgrade
+                      </code>
+                    </p>
+                    <p>
+                      {% trans 'Si toutefois vous n\'aviez pas acces à la console, suivez le lien suivant' %}
+                    </p>
+                    <p>
+                      <form action="/setup/upgrader/execute/" method="POST" target="update_target">
+                        <button class="update_button">{% trans 'Mise a jour' %}</button>
+                        <img style="display:none;" class="upgrade_loader" src="/skins/icons/loader111111.gif"/>
+                      </form>
+                      <iframe style="display:none;" src="about:blank" name="update_target"></iframe>
+                    </p>
+                    {% endif %}
                   {% else %}
                   <p>{% trans 'Progression de la mise a jour : ' %}</p>
                   <div id="progress_meter" style="text-align:center;width:100%;height:26px;border:1px solid #404040;position:relative;">