diff --git a/htdocs/core/boxes/box_actions.php b/htdocs/core/boxes/box_actions.php
index 64a2314560c..814dfacc5f3 100644
--- a/htdocs/core/boxes/box_actions.php
+++ b/htdocs/core/boxes/box_actions.php
@@ -162,7 +162,7 @@ class box_actions extends ModeleBoxes
 
 					$this->info_box_contents[$line][2] = array(
 						'td' => 'class="center nowraponall"',
-						'text' => dol_print_date($datelimite, "dayhour", 'tzuserrel'),
+						'text' => $datelimite ? dol_print_date($datelimite, "dayhour", 'tzuserrel') : '',
 						'asis' => 1
 					);
 
diff --git a/htdocs/core/boxes/box_graph_nb_ticket_last_x_days.php b/htdocs/core/boxes/box_graph_nb_ticket_last_x_days.php
index baa822dcf29..98aed557557 100644
--- a/htdocs/core/boxes/box_graph_nb_ticket_last_x_days.php
+++ b/htdocs/core/boxes/box_graph_nb_ticket_last_x_days.php
@@ -85,7 +85,7 @@ class box_graph_nb_ticket_last_x_days extends ModeleBoxes
 
 
 		$param_day = 'DOLUSERCOOKIE_ticket_last_days';
-		if ($_POST[$param_day]) {
+		if (!empty($_POST[$param_day])) {
 			if ($_POST[$param_day] >= 15) {
 				$days = 14;
 			} else {
diff --git a/htdocs/core/boxes/box_supplier_orders_awaiting_reception.php b/htdocs/core/boxes/box_supplier_orders_awaiting_reception.php
index 8125a848fd0..580ccdb373c 100644
--- a/htdocs/core/boxes/box_supplier_orders_awaiting_reception.php
+++ b/htdocs/core/boxes/box_supplier_orders_awaiting_reception.php
@@ -161,7 +161,7 @@ class box_supplier_orders_awaiting_reception extends ModeleBoxes
 
 					$this->info_box_contents[$line][] = array(
 						'td' => 'class="right"',
-						'text' => $delayIcon.'<span class="classfortooltip" title="'.$langs->trans('DateDeliveryPlanned').'"><i class="fa fa-dolly" ></i> '.dol_print_date($delivery_date, 'day', 'tzuserrel').'</span>',
+						'text' => $delayIcon.'<span class="classfortooltip" title="'.$langs->trans('DateDeliveryPlanned').'"><i class="fa fa-dolly" ></i> '.($delivery_date ? dol_print_date($delivery_date, 'day', 'tzuserrel') : '').'</span>',
 						'asis' => 1
 					);
 
diff --git a/htdocs/core/class/dolgraph.class.php b/htdocs/core/class/dolgraph.class.php
index ac2965668a2..a892c557b34 100644
--- a/htdocs/core/class/dolgraph.class.php
+++ b/htdocs/core/class/dolgraph.class.php
@@ -1384,7 +1384,7 @@ class DolGraph
 
 					$textoflegend = $arrayofgroupslegend[$i]['legendwithgroup'];
 				} else {
-					$textoflegend = $this->Legend[$i];
+					$textoflegend = !empty($this->Legend[$i]) ? $this->Legend[$i] : '';
 				}
 
 				if ($usecolorvariantforgroupby) {