Index: /extensions/NBC_UserAdvManager/branches/2.12/main.inc.php
===================================================================
--- /extensions/NBC_UserAdvManager/branches/2.12/main.inc.php	(revision 4162)
+++ /extensions/NBC_UserAdvManager/branches/2.12/main.inc.php	(revision 4168)
@@ -2,5 +2,5 @@
 /*
 Plugin Name: NBC UserAdvManager
-Version: 2.12.2
+Version: 2.12.3
 Description: Permet de renforcer les possibilités de gestion des utilisateurs - Enforce users management
 Plugin URI: http://fr.piwigo.org/ext/extension_view.php?eid=216
@@ -81,4 +81,6 @@
             Bug 1225 fixed - "Reminder" status don't change from "false" to "true" after the sent of a reminder email
             Some code beautify (SQL requests and HTML 4 strict for tpl)
+
+-- 2.12.3 : Bug 1226 fixed - "duplicate key error" when lastvisit table is not empty and on using Ghost Tracker init function 
 */
 
Index: /extensions/NBC_UserAdvManager/branches/2.12/admin/UserAdvManager_admin.php
===================================================================
--- /extensions/NBC_UserAdvManager/branches/2.12/admin/UserAdvManager_admin.php	(revision 4160)
+++ /extensions/NBC_UserAdvManager/branches/2.12/admin/UserAdvManager_admin.php	(revision 4168)
@@ -1147,7 +1147,6 @@
   INNER JOIN '.USER_INFOS_TABLE.' AS ui
     ON u.id = ui.user_id
-  INNER JOIN '.USER_LASTVISIT_TABLE.' AS ulv
-    ON u.id != ulv.user_id
-WHERE status != "webmaster"
+WHERE u.id NOT IN (SELECT user_id FROM '.USER_LASTVISIT_TABLE.')
+  AND status != "webmaster"
   AND status != "guest"
   AND status != "admin"