diff --git a/admin/admin_access_area.php b/admin/admin_access_area.php
index 8eda2c1..b9866a5 100644
--- a/admin/admin_access_area.php
+++ b/admin/admin_access_area.php
@@ -29,9 +29,7 @@
 $msg = '';
 
 
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 $day   = date("d");
 $month = date("m");
 $year  = date("Y");
diff --git a/admin/admin_accueil.php b/admin/admin_accueil.php
index db2bfcb..6759510 100644
--- a/admin/admin_accueil.php
+++ b/admin/admin_accueil.php
@@ -17,9 +17,7 @@
  */
 include "../include/admin.inc.php";
 $grr_script_name = "admin_accueil.php";
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 if ((authGetUserLevel(getUserName(), -1, 'area') < 4) && (authGetUserLevel(getUserName(), -1, 'user') !=  1))
 {
 	showAccessDenied($back);
diff --git a/admin/admin_admin_site.php b/admin/admin_admin_site.php
index cf81066..23f5e63 100644
--- a/admin/admin_admin_site.php
+++ b/admin/admin_admin_site.php
@@ -23,9 +23,8 @@
 	$id_site = get_default_site();
 if (!isset($id_site))
 	settype($id_site, "integer");
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
+
 check_access(6, $back);
 if (Settings::get("module_multisite") != "Oui")
 {
@@ -174,4 +173,4 @@ function site_go()
 		echo "</td></tr></table>";
 		?>
 	</body>
-	</html>
\ No newline at end of file
+	</html>
diff --git a/admin/admin_calend.php b/admin/admin_calend.php
index 76e0b89..4471a81 100644
--- a/admin/admin_calend.php
+++ b/admin/admin_calend.php
@@ -19,8 +19,7 @@
 include "../include/admin.inc.php";
 $grr_script_name = "admin_calend.php";
 
-$back = '';
-if (isset($_SERVER['HTTP_REFERER'])) $back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 
 // vérification des droits d'accès 
 if(authGetUserLevel(getUserName(),-1,'area') < 5)
diff --git a/admin/admin_calend2.php b/admin/admin_calend2.php
index fb5d579..eec24bd 100644
--- a/admin/admin_calend2.php
+++ b/admin/admin_calend2.php
@@ -18,9 +18,7 @@
 include "../include/admin.inc.php";
 $grr_script_name = "admin_calend2.php";
 
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 check_access(4, $back);
 // Initialisation
 $etape = isset($_POST["etape"]) ? $_POST["etape"] : NULL;
@@ -509,4 +507,4 @@ function validate_and_submit ()
 	echo "</td></tr></table>";
 	?>
 </body>
-</html>
\ No newline at end of file
+</html>
diff --git a/admin/admin_calend_ignore.php b/admin/admin_calend_ignore.php
index e9cc1d8..db3f6b2 100644
--- a/admin/admin_calend_ignore.php
+++ b/admin/admin_calend_ignore.php
@@ -18,9 +18,9 @@
 
 include "../include/admin.inc.php";
 $grr_script_name = "admin_calend_ignore.php";
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+
+$back = getBackUri();
+
 check_access(6, $back);
 # print the page header
 print_header("", "", "", $type="with_session");
diff --git a/admin/admin_calend_jour_cycle.php b/admin/admin_calend_jour_cycle.php
index 6bf5b3a..233866d 100644
--- a/admin/admin_calend_jour_cycle.php
+++ b/admin/admin_calend_jour_cycle.php
@@ -18,9 +18,7 @@
 
 include "../include/admin.inc.php";
 $grr_script_name = "admin_calend_jour_cycle.php";
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 $_SESSION['chemin_retour'] = "admin_calend_jour_cycle.php";
 $day   = date("d");
 $month = date("m");
diff --git a/admin/admin_calend_vacances_feries.php b/admin/admin_calend_vacances_feries.php
index f684c24..ccce91b 100644
--- a/admin/admin_calend_vacances_feries.php
+++ b/admin/admin_calend_vacances_feries.php
@@ -18,9 +18,7 @@
 
 include "../include/admin.inc.php";
 $grr_script_name = "admin_calend_vacances_feries.php";
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 check_access(6, $back);
 # print the page header
 print_header("", "", "", $type="with_session");
diff --git a/admin/admin_cgu.php b/admin/admin_cgu.php
index 6385043..0749fda 100644
--- a/admin/admin_cgu.php
+++ b/admin/admin_cgu.php
@@ -19,9 +19,7 @@
 include "../include/admin.inc.php";
 require_once("../include/pages.class.php");
 $grr_script_name = "admin_cgu.php";
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 $_SESSION['chemin_retour'] = "admin_cgu.php";
 $day   = date("d");
 $month = date("m");
@@ -96,4 +94,4 @@
 
 // fin de l'affichage de la colonne de droite
 echo '</td></tr></table>';
-?>
\ No newline at end of file
+?>
diff --git a/admin/admin_change_pwd.php b/admin/admin_change_pwd.php
index 714f68a..3516077 100644
--- a/admin/admin_change_pwd.php
+++ b/admin/admin_change_pwd.php
@@ -18,9 +18,7 @@
 
 include "../include/admin.inc.php";
 $grr_script_name = "admin_change_pwd.php";
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-    $back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 check_access(6, $back);
 // Restriction dans le cas d'une démo
 VerifyModeDemo();
diff --git a/admin/admin_config.php b/admin/admin_config.php
index 5e118a0..65b2194 100644
--- a/admin/admin_config.php
+++ b/admin/admin_config.php
@@ -18,9 +18,7 @@
 
 include "../include/admin.inc.php";
 $grr_script_name = "admin_config.php";
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 $_SESSION['chemin_retour'] = "admin_config.php";
 $day   = date("d");
 $month = date("m");
diff --git a/admin/admin_config_calend2.php b/admin/admin_config_calend2.php
index 066200c..c6d1e75 100644
--- a/admin/admin_config_calend2.php
+++ b/admin/admin_config_calend2.php
@@ -17,9 +17,7 @@
  */
 
 $grr_script_name = "admin_config_calend2.php";
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 check_access(6, $back);
 # print the page header
 print_header("", "", "", $type="with_session");
@@ -144,4 +142,4 @@
 echo "</td></tr></table>";
 ?>
 </body>
-</html>
\ No newline at end of file
+</html>
diff --git a/admin/admin_config_calend3.php b/admin/admin_config_calend3.php
index cdf2bb5..24aa680 100644
--- a/admin/admin_config_calend3.php
+++ b/admin/admin_config_calend3.php
@@ -96,8 +96,7 @@ function cal3($month, $year)
     $s .= "</table>\n";
     return $s;
 }
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 	check_access(6, $back);
 	print_header("", "", "", $type = "with_session");
 	// Affichage de la colonne de gauche
@@ -230,4 +229,4 @@ function check (select)
 		}
 	</script>
 </body>
-</html>
\ No newline at end of file
+</html>
diff --git a/admin/admin_config_imap.php b/admin/admin_config_imap.php
index edf08c8..e770a5c 100644
--- a/admin/admin_config_imap.php
+++ b/admin/admin_config_imap.php
@@ -45,9 +45,7 @@
 		$grrSettings['imap_statut'] = $_POST['imap_statut'];
 	}
 }
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 if ((isset($imap_restrictions)) && ($imap_restrictions == true))
 {
 	showAccessDenied($back);
@@ -311,4 +309,4 @@
 	echo "</td></tr></table>";
 ?>
 </body>
-</html>
\ No newline at end of file
+</html>
diff --git a/admin/admin_config_ldap.php b/admin/admin_config_ldap.php
index 805cf9d..f7d3f7e 100644
--- a/admin/admin_config_ldap.php
+++ b/admin/admin_config_ldap.php
@@ -162,9 +162,7 @@
 			<?php
 			die();
 		};
-		$back = '';
-		if (isset($_SERVER['HTTP_REFERER']))
-			$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+		$back = getBackUri();
 		if ((isset($ldap_restrictions)) && ($ldap_restrictions == true))
 		{
 			showAccessDenied($back);
diff --git a/admin/admin_config_sso.php b/admin/admin_config_sso.php
index 6416346..89a251a 100644
--- a/admin/admin_config_sso.php
+++ b/admin/admin_config_sso.php
@@ -19,9 +19,7 @@
 include "../include/admin.inc.php";
 $grr_script_name = "admin_config_sso.php";
 
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 if ((isset($sso_restrictions)) && ($sso_restrictions==true))
 {
 	showAccessDenied($back);
@@ -138,8 +136,7 @@
 		echo "Erreur lors de l'enregistrement de sso_redirection_accueil_grr !<br />";
 }
 
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 if ((authGetUserLevel(getUserName(), -1) < 6) && ($valid != 'yes'))
 {
 	showAccessDenied($back);
diff --git a/admin/admin_confirm_change_date_bookings.php b/admin/admin_confirm_change_date_bookings.php
index ecdc174..bdcdd71 100644
--- a/admin/admin_confirm_change_date_bookings.php
+++ b/admin/admin_confirm_change_date_bookings.php
@@ -19,9 +19,8 @@
 
 include "../include/admin.inc.php";
 $grr_script_name = "admin_confirm_change_date_bookings.php";
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+
+$back = getBackUri();
 unset($display);
 $display = isset($_GET["display"]) ? $_GET["display"] : NULL;
 $day   = date("d");
diff --git a/admin/admin_corresp_statut.php b/admin/admin_corresp_statut.php
index 02c1b5e..5ff710e 100644
--- a/admin/admin_corresp_statut.php
+++ b/admin/admin_corresp_statut.php
@@ -17,9 +17,7 @@
 
 include "../include/admin.inc.php";
 $grr_script_name = "admin_config_sso.php";
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 if (Settings::get("sso_ac_corr_profil_statut") != 'y')
 {
 	showAccessDenied($back);
@@ -76,9 +74,7 @@
 	else
 		$msg = get_vocab("message_records");
 }
-$back = "";
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 //print the page header
 print_header("", "", "", $type="with_session");
 // Affichage de la colonne de gauche
diff --git a/admin/admin_delete_entry_after.php b/admin/admin_delete_entry_after.php
index e07b688..322643e 100644
--- a/admin/admin_delete_entry_after.php
+++ b/admin/admin_delete_entry_after.php
@@ -17,9 +17,7 @@
 
 include "../include/admin.inc.php";
 $grr_script_name = "admin_delete_entry_after.php";
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 $_SESSION['chemin_retour'] = "admin_config.php";
 
 if (!Settings::load()) {
@@ -132,4 +130,4 @@
 
 echo "<a href=\"admin_calend.php\">".get_vocab('returnprev')."</a><p>";
 
-include "../include/trailer.inc.php"; ?>
\ No newline at end of file
+include "../include/trailer.inc.php"; ?>
diff --git a/admin/admin_delete_entry_before.php b/admin/admin_delete_entry_before.php
index eebc5d7..8a8f0fb 100644
--- a/admin/admin_delete_entry_before.php
+++ b/admin/admin_delete_entry_before.php
@@ -17,9 +17,7 @@
 
 include "../include/admin.inc.php";
 $grr_script_name = "admin_delete_entry_before.php";
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 $_SESSION['chemin_retour'] = "admin_config.php";
 
 if (!Settings::load()) {
@@ -130,4 +128,4 @@
 
 echo "<a href=\"admin_calend.php\">".get_vocab('returnprev')."</a><p>";
 
-include "../include/trailer.inc.php"; ?>
\ No newline at end of file
+include "../include/trailer.inc.php"; ?>
diff --git a/admin/admin_edit_room.php b/admin/admin_edit_room.php
index a151374..161bb87 100644
--- a/admin/admin_edit_room.php
+++ b/admin/admin_edit_room.php
@@ -86,9 +86,7 @@
 	$moderate = 0;
 settype($type_affichage_reser, "integer");
 
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 
 if (isset($_POST["change_room_and_back"]))
 {
diff --git a/admin/admin_email_manager.php b/admin/admin_email_manager.php
index 9e20725..00f8867 100644
--- a/admin/admin_email_manager.php
+++ b/admin/admin_email_manager.php
@@ -24,9 +24,8 @@
 	settype($room,"integer");
 if (!isset($id_area))
 	settype($id_area,"integer");
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+
+$back = getBackUri();
 check_access(4, $back);
 // tableau des ressources auxquelles l'utilisateur n'a pas accès
 $tab_rooms_noaccess = verif_acces_ressource(getUserName(), 'all');
@@ -278,4 +277,4 @@ function room_go()
 echo "</td></tr></table>";
 ?>
 </body>
-</html>
\ No newline at end of file
+</html>
diff --git a/admin/admin_import_entries_csv_udt.php b/admin/admin_import_entries_csv_udt.php
index 4741ced..20d721e 100644
--- a/admin/admin_import_entries_csv_udt.php
+++ b/admin/admin_import_entries_csv_udt.php
@@ -18,9 +18,7 @@
 include "../include/admin.inc.php";
 $grr_script_name = "admin_import_entries_csv_udt.php";
 
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 $_SESSION['chemin_retour'] = "admin_config.php";
 
 if (!Settings::load()) {
@@ -604,4 +602,4 @@ function entre_reservation($room_id,$jour_semaine,$name,$description,
 		// Retour au calendrier
 }
 
-?>
\ No newline at end of file
+?>
diff --git a/admin/admin_import_users_csv.php b/admin/admin_import_users_csv.php
index 0f82e22..3f89932 100644
--- a/admin/admin_import_users_csv.php
+++ b/admin/admin_import_users_csv.php
@@ -19,9 +19,7 @@
 include "../include/admin.inc.php";
 $grr_script_name = "admin_import_users_csv.php";
 
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 if ((authGetUserLevel(getUserName(), -1) < 6) && (authGetUserLevel(getUserName(), -1, 'user') !=  1))
 {
 	showAccessDenied($back);
diff --git a/admin/admin_import_users_elycee.php b/admin/admin_import_users_elycee.php
index 7a06f1e..635c0e9 100644
--- a/admin/admin_import_users_elycee.php
+++ b/admin/admin_import_users_elycee.php
@@ -18,9 +18,7 @@
 include "../include/admin.inc.php";
 $grr_script_name = "admin_import_users_elycee.php";
 
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 if ((authGetUserLevel(getUserName(), -1) < 6) && (authGetUserLevel(getUserName(), -1, 'user') !=  1))
 {
 	showAccessDenied($back);
@@ -286,4 +284,4 @@
 	 echo "</td></tr></table>"; // fin de la colonne droite
     ?>
     </body>
-	</html>
\ No newline at end of file
+	</html>
diff --git a/admin/admin_import_xml_edt.php b/admin/admin_import_xml_edt.php
index 6b5ffd6..64869d2 100644
--- a/admin/admin_import_xml_edt.php
+++ b/admin/admin_import_xml_edt.php
@@ -18,9 +18,7 @@
 include "../include/admin.inc.php";
 $grr_script_name = "admin_import_xml_edt.php";
 
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 $_SESSION['chemin_retour'] = "admin_config.php";
 
 if (!Settings::load()) {
@@ -539,4 +537,4 @@ function entre_reservation($room_id,$jour_semaine,$name,$description,
 		// Retour au calendrier
 }
 
-?>
\ No newline at end of file
+?>
diff --git a/admin/admin_maj.php b/admin/admin_maj.php
index daf846a..b135009 100644
--- a/admin/admin_maj.php
+++ b/admin/admin_maj.php
@@ -203,9 +203,7 @@ function traite_requete($requete = "")
 			die();
 }
 
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 
 if ((authGetUserLevel(getUserName(),-1) < 6) && ($valid != 'yes') && $connexionAdminMAJ == 1)
 {
@@ -1126,4 +1124,4 @@ function traite_requete($requete = "")
 	echo "</script>";
 	echo "</body>";
 	echo "</html>";
-}
\ No newline at end of file
+}
diff --git a/admin/admin_overload.php b/admin/admin_overload.php
index 903beb6..434acef 100644
--- a/admin/admin_overload.php
+++ b/admin/admin_overload.php
@@ -17,9 +17,9 @@
 
 include "../include/admin.inc.php";
 $grr_script_name = "admin_overload.php";
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+
+$back = getBackUri();
+
 $day   = date("d");
 $month = date("m");
 $year  = date("Y");
diff --git a/admin/admin_purge_accounts.php b/admin/admin_purge_accounts.php
index 254af14..0be8755 100644
--- a/admin/admin_purge_accounts.php
+++ b/admin/admin_purge_accounts.php
@@ -17,9 +17,8 @@
 
 include "../include/admin.inc.php";
 $grr_script_name = "admin_user.php";
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
+
 $display = isset($_GET["display"]) ? $_GET["display"] : NULL;
 $order_by = isset($_GET["order_by"]) ? $_GET["order_by"] : NULL;
 $msg = '';
diff --git a/admin/admin_right.php b/admin/admin_right.php
index 176157b..f670bd1 100644
--- a/admin/admin_right.php
+++ b/admin/admin_right.php
@@ -17,9 +17,9 @@
 
 include "../include/admin.inc.php";
 $grr_script_name = "admin_right.php";
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+
+$back = getBackUri();
+
 $id_area = isset($_POST["id_area"]) ? $_POST["id_area"] : (isset($_GET["id_area"]) ? $_GET["id_area"] : NULL);
 $room = isset($_POST["room"]) ? $_POST["room"] : (isset($_GET["room"]) ? $_GET["room"] : NULL);
 if (isset($room))
@@ -503,4 +503,4 @@ function room_go()
 		echo "</td></tr></table>";
 		?>
 	</body>
-	</html>
\ No newline at end of file
+	</html>
diff --git a/admin/admin_right_admin.php b/admin/admin_right_admin.php
index 7634e33..1995b34 100644
--- a/admin/admin_right_admin.php
+++ b/admin/admin_right_admin.php
@@ -21,9 +21,9 @@
 $id_area = isset($_POST["id_area"]) ? $_POST["id_area"] : (isset($_GET["id_area"]) ? $_GET["id_area"] : NULL);
 if (!isset($id_area))
 	settype($id_area,"integer");
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+
+$back = getBackUri();
+
 $day   = date("d");
 $month = date("m");
 $year  = date("Y");
@@ -236,4 +236,4 @@ function area_go()
 		echo "</td></tr></table>";
 		?>
 	</body>
-	</html>
\ No newline at end of file
+	</html>
diff --git a/admin/admin_room.php b/admin/admin_room.php
index 0b0072e..aa1d318 100644
--- a/admin/admin_room.php
+++ b/admin/admin_room.php
@@ -26,9 +26,7 @@
 if (!isset($id_site))
 	$id_site = isset($_POST['id_site']) ? $_POST['id_site'] : (isset($_GET['id_site']) ? $_GET['id_site'] : -1);
 settype($id_site,"integer");
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 $day   = date("d");
 $month = date("m");
 $year  = date("Y");
@@ -345,4 +343,4 @@ function site_go()
 	echo "</td></tr></table>\n";
 	?>
 </body>
-</html>
\ No newline at end of file
+</html>
diff --git a/admin/admin_room_del.php b/admin/admin_room_del.php
index e9550b7..98982a8 100644
--- a/admin/admin_room_del.php
+++ b/admin/admin_room_del.php
@@ -29,8 +29,7 @@
 	settype($id_area,"integer");
 if (isset($id_site))
 	settype($id_site,"integer");
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 if ($type == "room")
 {
 	if ((authGetUserLevel(getUserName(),$room) < 4) || (!verif_acces_ressource(getUserName(), $room)))
@@ -137,4 +136,4 @@
 }
 ?>
 </body>
-</html>
\ No newline at end of file
+</html>
diff --git a/admin/admin_save_mysql.php b/admin/admin_save_mysql.php
index 1070684..3838583 100644
--- a/admin/admin_save_mysql.php
+++ b/admin/admin_save_mysql.php
@@ -51,9 +51,7 @@
 else
 {
 	include "../include/admin.inc.php";
-	$back = '';
-	if (isset($_SERVER['HTTP_REFERER']))
-		$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+	$back = getBackUri();
 	if (authGetUserLevel(getUserName(),-1) < 6)
 	{
 		showAccessDenied($back);
@@ -193,4 +191,4 @@ function mysql_version()
 }
 $fd.="#********* fin du fichier ***********";
 echo $fd;
-?>
\ No newline at end of file
+?>
diff --git a/admin/admin_site.php b/admin/admin_site.php
index c2d5fe6..55c8c9a 100644
--- a/admin/admin_site.php
+++ b/admin/admin_site.php
@@ -328,17 +328,13 @@ function check_right($id)
 	// Debut de l'affichage de la page
 	include_once('../include/admin.inc.php');
 	$grr_script_name = 'admin_site.php';
-	if (authGetUserLevel(getUserName(), -1, 'site') < 4)
-	{
-		$back = '';
-		if (isset($_SERVER['HTTP_REFERER']))
-			$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+	$back = getBackUri();
+	
+	if (authGetUserLevel(getUserName(), -1, 'site') < 4){
 		showAccessDenied($back);
 		exit();
 	}
-	$back = "";
-	if (isset($_SERVER['HTTP_REFERER']))
-		$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+	
 	// print the page header
 	print_header("", "", "", $type="with_session");
 	// Affichage de la colonne de gauche
@@ -381,4 +377,4 @@ function check_right($id)
 	echo "</td></tr></table>\n";
 	?>
 </body>
-</html>
\ No newline at end of file
+</html>
diff --git a/admin/admin_type.php b/admin/admin_type.php
index 1a5cf36..17c0774 100644
--- a/admin/admin_type.php
+++ b/admin/admin_type.php
@@ -16,9 +16,7 @@
  */
 include "../include/admin.inc.php";
 $grr_script_name = "admin_type.php";
-$back = "";
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 check_access(6, $back);
 if ((isset($_GET['msg'])) && isset($_SESSION['displ_msg']) && ($_SESSION['displ_msg'] == 'yes') )
 	$msg = $_GET['msg'];
diff --git a/admin/admin_type_area.php b/admin/admin_type_area.php
index 2a271ab..6891b5b 100644
--- a/admin/admin_type_area.php
+++ b/admin/admin_type_area.php
@@ -20,16 +20,12 @@
 $grr_script_name = "admin_type_area.php";
 // Initialisation
 $id_area = isset($_GET["id_area"]) ? $_GET["id_area"] : NULL;
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 $day   = date("d");
 $month = date("m");
 $year  = date("Y");
 check_access(4, $back);
-$back = "";
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+
 // Gestion du retour à la page précédente sans enregistrement
 if (isset($_GET['change_done']))
 {
diff --git a/admin/admin_type_modify.php b/admin/admin_type_modify.php
index 4c8ac82..7da9000 100644
--- a/admin/admin_type_modify.php
+++ b/admin/admin_type_modify.php
@@ -19,9 +19,7 @@
 include "../include/admin.inc.php";
 $grr_script_name = "admin_type_modify.php";
 $ok = NULL;
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 $day   = date("d");
 $month = date("m");
 $year  = date("Y");
diff --git a/admin/admin_user.php b/admin/admin_user.php
index 8375ef9..f7c3a52 100644
--- a/admin/admin_user.php
+++ b/admin/admin_user.php
@@ -18,9 +18,7 @@
 
 include "../include/admin.inc.php";
 $grr_script_name = "admin_user.php";
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 $display = isset($_GET["display"]) ? $_GET["display"] : NULL;
 $order_by = isset($_GET["order_by"]) ? $_GET["order_by"] : NULL;
 $msg = '';
diff --git a/admin/admin_user_mdp_facile.php b/admin/admin_user_mdp_facile.php
index 747ba5c..c6cd763 100644
--- a/admin/admin_user_mdp_facile.php
+++ b/admin/admin_user_mdp_facile.php
@@ -17,9 +17,7 @@
 
 include "../include/admin.inc.php";
 $grr_script_name = "admin_user_mdp_facile.php";
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 $display = isset($_GET["display"]) ? $_GET["display"] : NULL;
 $order_by = isset($_GET["order_by"]) ? $_GET["order_by"] : NULL;
 $msg = '';
diff --git a/admin/admin_user_modify.php b/admin/admin_user_modify.php
index 123560e..83dbbd0 100644
--- a/admin/admin_user_modify.php
+++ b/admin/admin_user_modify.php
@@ -17,9 +17,8 @@
  */
 include "../include/admin.inc.php";
 $grr_script_name = "admin_user_modify.php";
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
+
 if ((authGetUserLevel(getUserName(), -1) < 6) && (authGetUserLevel(getUserName(), -1, 'user') !=  1))
 {
 	showAccessDenied($back);
diff --git a/admin/admin_view_connexions.php b/admin/admin_view_connexions.php
index 515f998..25c6d42 100644
--- a/admin/admin_view_connexions.php
+++ b/admin/admin_view_connexions.php
@@ -17,9 +17,7 @@
  */
 include "../include/admin.inc.php";
 $grr_script_name = "admin_view_connexions.php";
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 $day   = date("d");
 $month = date("m");
 $year  = date("Y");
diff --git a/del_entry.php b/del_entry.php
index b539386..8f1d04f 100644
--- a/del_entry.php
+++ b/del_entry.php
@@ -49,9 +49,7 @@
 	$month = strftime("%m", $info["start_time"]);
 	$year  = strftime("%Y", $info["start_time"]);
 	$area  = mrbsGetRoomArea($info["room_id"]);
-	$back = "";
-	if (isset($_SERVER['HTTP_REFERER']))
-		$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+	$back = getBackUri();
 	if (authGetUserLevel(getUserName(), -1) < 1)
 	{
 		showAccessDenied($back);
diff --git a/edit_entry.php b/edit_entry.php
index d04681a..822b996 100644
--- a/edit_entry.php
+++ b/edit_entry.php
@@ -86,9 +86,7 @@
 $qui_peut_reserver_pour  = grr_sql_query1("SELECT qui_peut_reserver_pour FROM ".TABLE_PREFIX."_room WHERE id='".$room."'");
 $active_cle  = grr_sql_query1("SELECT active_cle FROM ".TABLE_PREFIX."_room WHERE id='".$room."'");
 $periodiciteConfig = Settings::get("periodicite");
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars( $_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 $longueur_liste_ressources_max = Settings::get("longueur_liste_ressources_max");
 if ($longueur_liste_ressources_max == '')
 	$longueur_liste_ressources_max = 20;
@@ -1291,4 +1289,4 @@ function changeRooms( formObj )
 	<?php
 	include "include/trailer.inc.php";
 	include "footer.php";
-	?>
\ No newline at end of file
+	?>
diff --git a/edit_entry_handler.php b/edit_entry_handler.php
index 7dd32ad..1cc9965 100644
--- a/edit_entry_handler.php
+++ b/edit_entry_handler.php
@@ -167,12 +167,7 @@
 	include "include/trailer.inc.php";
 	die();
 }
-$back = (isset($_SERVER['HTTP_REFERER']))? htmlspecialchars($_SERVER['HTTP_REFERER']) :'';
-//if (isset($_SERVER['HTTP_REFERER']))
-//	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
-// page de retour
-$ret_page = (isset($_GET['page_ret']))? $_GET['page_ret'] : $back;
-
+$back = getBackUri();
 $area = mrbsGetRoomArea($_GET['rooms'][0]);
 $overload_data = array();
 $overload_fields_list = mrbsOverloadGetFieldslist($area);
diff --git a/include/planning_init.inc.php b/include/planning_init.inc.php
index 46a59e3..8d40d2a 100644
--- a/include/planning_init.inc.php
+++ b/include/planning_init.inc.php
@@ -66,9 +66,7 @@
 	$day = 1;
 */
 // Lien de retour
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 
 // Type de session
 if ((Settings::get("authentification_obli") == 0) && (getUserName() == ''))
@@ -166,4 +164,4 @@
 	echo '<div id="print_planning">'.PHP_EOL;
 }
 
-?>
\ No newline at end of file
+?>
diff --git a/include/session.inc.php b/include/session.inc.php
index 091cc7e..a077e55 100644
--- a/include/session.inc.php
+++ b/include/session.inc.php
@@ -653,6 +653,10 @@ function grr_opensession($_login, $_password, $_user_ext_authentifie = '', $tab_
 	$_SESSION['default_room'] = $row[7];
 else
 	$_SESSION['default_room'] = Settings::get("default_room");
+
+// Enregistrement de la page courante pour le retour en arriere
+$_SESSION['back'] = [getRequestUri(), ''];
+
 if ($row[8] !='')
 	$_SESSION['default_style'] = $row[8];
 else
@@ -828,6 +832,11 @@ function grr_resumeSession()
 		// Resuming session
 	session_name(SESSION_NAME);
 	@session_start();
+
+	// Enregistrement de la page courante pour le retour en arriere
+	$_SESSION['back'][1] = $_SESSION['back'][0];
+	$_SESSION['back'][0] = getRequestUri();
+
 	if ((Settings::get('sso_statut') == 'lcs') and (!isset($_SESSION['est_authentifie_sso'])) and ($_SESSION['source_login'] == "ext"))
 		return (false);
 		// La session est-elle expirée
@@ -1208,6 +1217,49 @@ function grr_getinfo_ldap($_dn, $_login, $_password)
 	// Return infos
 	return array($l_nom, $l_prenom, $l_email);
 }
+
+/**
+ * Permet de récupérer l'uri demandé
+ */
+function getRequestUri()
+{
+	global $grr_script_name;
+	$RequestUri = "";
+	if (isset($_SERVER['REQUEST_URI']))
+		$RequestUri = $_SERVER['REQUEST_URI'];
+	else if (isset($_ENV['REQUEST_URI']))
+		$RequestUri = $_ENV['REQUEST_URI'];
+	else if (isset($_SERVER['HTTP_X_REWRITE_URL']))
+		$RequestUri = $_SERVER['HTTP_X_REWRITE_URL'];
+	else
+	{
+		if (!isset($_SERVER['QUERY_STRING']))
+			$_SERVER['QUERY_STRING'] = "";
+		if ((Settings::get("use_grr_url") == "y") && (Settings::get("grr_url") != ""))
+		{
+			if (substr(Settings::get("grr_url"), -1) != "/")
+				$ad_signe = "/";
+			else
+				$ad_signe = "";
+			$RequestUri = Settings::get("grr_url").$ad_signe.$grr_script_name.$_SERVER['QUERY_STRING'];
+		}
+		else
+		{
+			if (isset($_SERVER['PHP_SELF']))
+				$RequestUri = $_SERVER['PHP_SELF'].$_SERVER['QUERY_STRING'];
+		}
+	}
+	return $RequestUri;
+}
+
+/**
+ * Permet de récupérer l'uri de la page précédente
+ */
+function getBackUri()
+{
+	return htmlspecialchars($_SESSION['back'][1]);
+}
+
 // On fabrique l'url
 $url = rawurlencode(str_replace('&amp;','&',get_request_uri()));
 ?>
diff --git a/lasso/defederate.php b/lasso/defederate.php
index df652dc..561823b 100644
--- a/lasso/defederate.php
+++ b/lasso/defederate.php
@@ -55,4 +55,4 @@
   echo get_vocab('lasso_defederated');
 }
 echo "<br />";
-echo "<a href='{$_SERVER['HTTP_REFERER']}'>".get_vocab('back').'</a>';
+echo "<a href='".getBackUri()."'>".get_vocab('back').'</a>';
diff --git a/lasso/federate.php b/lasso/federate.php
index 19dc31d..507fd6e 100644
--- a/lasso/federate.php
+++ b/lasso/federate.php
@@ -55,7 +55,7 @@
       echo get_vocab('lasso_please_connect');
     }
   echo "<br />";
-  echo "<a href='{$_SERVER['HTTP_REFERER']}'>".get_vocab('back').'</a>';
+  echo "<a href='".getBackUri()."'>".get_vocab('back').'</a>';
 }
 else
 {
diff --git a/moderate_entry_do.php b/moderate_entry_do.php
index ef4528c..e6f470b 100644
--- a/moderate_entry_do.php
+++ b/moderate_entry_do.php
@@ -44,9 +44,7 @@
 	$type_session = "with_session";
 // On vérifie que l'utilisateur a bien le droit d'être ici
 $room_id = grr_sql_query1("SELECT room_id FROM ".TABLE_PREFIX."_entry WHERE id='".$_POST['id']."'");
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 if (authGetUserLevel(getUserName(), $room_id) < 3)
 {
 	showAccessDenied($back);
diff --git a/my_account.php b/my_account.php
index c0f73b1..a398de8 100644
--- a/my_account.php
+++ b/my_account.php
@@ -37,9 +37,7 @@
 $year = isset($_POST['year']) ? $_POST['year'] : (isset($_GET['year']) ? $_GET['year'] : date('Y'));
 include_once('include/language.inc.php');
 include "include/resume_session.php";
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 $user_login = isset($_POST['user_login']) ? $_POST['user_login'] : ($user_login = isset($_GET['user_login']) ? $_GET['user_login'] : NULL);
 $valid = isset($_POST['valid']) ? $_POST['valid'] : NULL;
 $msg = '';
@@ -608,4 +606,4 @@ function modifier_liste_ressources(action){
                       </div>                        
 					</body>
 					</html>';
-					?>
\ No newline at end of file
+					?>
diff --git a/report.php b/report.php
index ae58d49..8d00177 100644
--- a/report.php
+++ b/report.php
@@ -40,9 +40,7 @@
 else
 	$_GET['pview'] = 1;
 //Récupération des informations relatives au serveur.
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 //Renseigne les droits de l'utilisateur, si les droits sont insufisants, l'utilisateur est avertit.
 if (!verif_access_search(getUserName()))
 {
diff --git a/validation.php b/validation.php
index 619d210..1ab34a2 100644
--- a/validation.php
+++ b/validation.php
@@ -43,9 +43,7 @@
 	$class_image = "print_image";
 else
 	$class_image = "image";
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 if (($settings->get("authentification_obli") == 0) && (getUserName() == ''))
 	$type_session = "no_session";
 else
diff --git a/view_entry.php b/view_entry.php
index b4514ca..e21db4a 100644
--- a/view_entry.php
+++ b/view_entry.php
@@ -54,10 +54,9 @@
 }
 else
 	die();
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars_decode($_SERVER['HTTP_REFERER']);
-// echo $back;
+
+$back = getBackUri();
+
 if (isset($_GET["action_moderate"])){
     // ici on a l'id de la réservation, on peut donc construire un lien de retour complet, à la bonne date et avec la ressource précise
     /* $page = $_GET["page"];
diff --git a/year.php b/year.php
index 6453c96..2f6b9d0 100644
--- a/year.php
+++ b/year.php
@@ -99,9 +99,7 @@
 	$type_session = "no_session";
 else
 	$type_session = "with_session";
-$back = '';
-if (isset($_SERVER['HTTP_REFERER']))
-	$back = htmlspecialchars($_SERVER['HTTP_REFERER']);
+$back = getBackUri();
 if (check_begin_end_bookings($day, $from_month, $from_year))
 {
 	showNoBookings($day, $from_month, $from_year, $back);