diff --git a/htdocs/commande/card.php b/htdocs/commande/card.php
index 12150f9a61e..27c333eec21 100644
--- a/htdocs/commande/card.php
+++ b/htdocs/commande/card.php
@@ -207,13 +207,13 @@ if (empty($reshook))
 		if ($datecommande == '') {
 			setEventMessage($langs->trans('ErrorFieldRequired', $langs->transnoentities('Date')), 'errors');
 			$action = 'create';
-			$error ++;
+			$error++;
 		}
 
 		if ($socid < 1) {
 			setEventMessage($langs->trans("ErrorFieldRequired", $langs->transnoentitiesnoconv("Customer")), 'errors');
 			$action = 'create';
-			$error ++;
+			$error++;
 		}
 
 		if (! $error) {
@@ -334,7 +334,7 @@ if (empty($reshook))
 								$result = $object->addline($desc, $lines [$i]->subprice, $lines [$i]->qty, $lines [$i]->tva_tx, $lines [$i]->localtax1_tx, $lines [$i]->localtax2_tx, $lines [$i]->fk_product, $lines [$i]->remise_percent, $lines [$i]->info_bits, $lines [$i]->fk_remise_except, 'HT', 0, $date_start, $date_end, $product_type, $lines [$i]->rang, $lines [$i]->special_code, $fk_parent_line, $lines [$i]->fk_fournprice, $lines [$i]->pa_ht, $label, $array_option);
 
 								if ($result < 0) {
-									$error ++;
+									$error++;
 									break;
 								}
 
@@ -349,14 +349,14 @@ if (empty($reshook))
 							$reshook = $hookmanager->executeHooks('createFrom', $parameters, $object, $action); // Note that $action and $object may have been
 							                                                                               // modified by hook
 							if ($reshook < 0)
-								$error ++;
+								$error++;
 						} else {
 							setEventMessage($srcobject->error, 'errors');
-							$error ++;
+							$error++;
 						}
 					} else {
 						setEventMessage($object->error, 'errors');
-						$error ++;
+						$error++;
 					}
 				} else {
 					// Required extrafield left blank, error message already defined by setOptionalsFromPost()
@@ -390,7 +390,7 @@ if (empty($reshook))
 					$result = $object->add_contact(GETPOST('contactid'), 'CUSTOMER', 'external');
 					if ($result < 0) {
 						setEventMessage($langs->trans("ErrorFailedToAddContact"), 'errors');
-						$error ++;
+						$error++;
 					}
 				}
 
@@ -554,24 +554,24 @@ if (empty($reshook))
 
 		if (empty($idprod) && ($price_ht < 0) && ($qty < 0)) {
 			setEventMessage($langs->trans('ErrorBothFieldCantBeNegative', $langs->transnoentitiesnoconv('UnitPriceHT'), $langs->transnoentitiesnoconv('Qty')), 'errors');
-			$error ++;
+			$error++;
 		}
 		if (GETPOST('prod_entry_mode') == 'free' && empty($idprod) && GETPOST('type') < 0) {
 			setEventMessage($langs->trans('ErrorFieldRequired', $langs->transnoentitiesnoconv('Type')), 'errors');
-			$error ++;
+			$error++;
 		}
 		if (GETPOST('prod_entry_mode') == 'free' && empty($idprod) && (! ($price_ht >= 0) || $price_ht == '')) 	// Unit price can be 0 but not ''
 		{
 			setEventMessage($langs->trans("ErrorFieldRequired", $langs->transnoentitiesnoconv("UnitPriceHT")), 'errors');
-			$error ++;
+			$error++;
 		}
 		if ($qty == '') {
 			setEventMessage($langs->trans('ErrorFieldRequired', $langs->transnoentitiesnoconv('Qty')), 'errors');
-			$error ++;
+			$error++;
 		}
 		if (GETPOST('prod_entry_mode') == 'free' && empty($idprod) && empty($product_desc)) {
 			setEventMessage($langs->trans('ErrorFieldRequired', $langs->transnoentitiesnoconv('Description')), 'errors');
-			$error ++;
+			$error++;
 		}
 
 		if (! $error && ($qty >= 0) && (! empty($product_desc) || ! empty($idprod))) {
@@ -826,7 +826,7 @@ if (empty($reshook))
 
 			if ($price_min && (price2num($pu_ht) * (1 - price2num(GETPOST('remise_percent')) / 100) < price2num($price_min))) {
 				setEventMessage($langs->trans("CantBeLessThanMinPrice", price(price2num($price_min, 'MU'), 0, $langs, 0, 0, - 1, $conf->currency)), 'errors');
-				$error ++;
+				$error++;
 			}
 		} else {
 			$type = GETPOST('type');
@@ -835,7 +835,7 @@ if (empty($reshook))
 			// Check parameters
 			if (GETPOST('type') < 0) {
 				setEventMessage($langs->trans("ErrorFieldRequired", $langs->transnoentitiesnoconv("Type")), 'errors');
-				$error ++;
+				$error++;
 			}
 		}
 
@@ -1137,10 +1137,10 @@ if (empty($reshook))
 			if (empty($reshook)) {
 				$result = $object->insertExtraFields();
 				if ($result < 0) {
-					$error ++;
+					$error++;
 				}
 			} else if ($reshook < 0)
-				$error ++;
+				$error++;
 		}
 
 		if ($error)
diff --git a/htdocs/core/tpl/objectline_create.tpl.php b/htdocs/core/tpl/objectline_create.tpl.php
index 6037f6c77c9..e3f2431783f 100644
--- a/htdocs/core/tpl/objectline_create.tpl.php
+++ b/htdocs/core/tpl/objectline_create.tpl.php
@@ -153,12 +153,12 @@ else {
 
 		if (empty($senderissupplier))
 		{
-			$form->select_produits('', 'idprod', $filtertype, $conf->product->limit_size, $buyer->price_level, 1, 2, '', 1, array(),$buyer->id);
+			$form->select_produits(GETPOST('idprod'), 'idprod', $filtertype, $conf->product->limit_size, $buyer->price_level, 1, 2, '', 1, array(),$buyer->id);
 		}
 		else
 		{
 			$ajaxoptions=array(
-					'update' => array('qty'=>'qty','remise_percent' => 'discount'),	// html id tag will be edited with which ajax json response key
+					'update' => array('qty'=>'qty','remise_percent' => 'discount'),	// html id tags that will be edited with which ajax json response key
 					'option_disabled' => 'addPredefinedProductButton',	// html id to disable once select is done
 					'warning' => $langs->trans("NoPriceDefinedForThisSupplier") // translation of an error saved into var 'error'
 			);
@@ -192,23 +192,16 @@ else {
 	</td>
 
 	<td align="right"><?php
-	if (GETPOST('prod_entry_mode') != 'predef')
-	{
-		if ($seller->tva_assuj == "0") echo '<input type="hidden" name="tva_tx" id="tva_tx" value="0">0';
-		else echo $form->load_tva('tva_tx', (isset($_POST["tva_tx"])?$_POST["tva_tx"]:-1), $seller, $buyer);
-	}
+	if ($seller->tva_assuj == "0") echo '<input type="hidden" name="tva_tx" id="tva_tx" value="0">0';
+	else echo $form->load_tva('tva_tx', (isset($_POST["tva_tx"])?$_POST["tva_tx"]:-1), $seller, $buyer);
 	?>
 	</td>
 	<td align="right">
-	<?php if (GETPOST('prod_entry_mode') != 'predef') { ?>
 	<input type="text" size="5" name="price_ht" id="price_ht" class="flat" value="<?php echo (isset($_POST["price_ht"])?$_POST["price_ht"]:''); ?>">
-	<?php } ?>
 	</td>
 	<?php if (! empty($inputalsopricewithtax)) { ?>
 	<td align="right">
-	<?php if (GETPOST('prod_entry_mode') != 'predef') { ?>
 	<input type="text" size="5" name="price_ttc" id="price_ttc" class="flat" value="<?php echo (isset($_POST["price_ttc"])?$_POST["price_ttc"]:''); ?>">
-	<?php } ?>
 	</td>
 	<?php } ?>
 	<td align="right"><input type="text" size="2" name="qty" id="qty" class="flat" value="<?php echo (isset($_POST["qty"])?$_POST["qty"]:1); ?>">
@@ -273,7 +266,7 @@ else {
 </tr>
 
 <?php
-if (! empty($conf->service->enabled) && $dateSelector && GETPOST('type') != '0')
+if ((! empty($conf->service->enabled) || ($object->element == 'contrat')) && $dateSelector && GETPOST('type') != '0')	// We show date field if required
 {
 	if(! empty($conf->global->MAIN_VIEW_LINE_NUMBER)) $colspan = 10;
 	else $colspan = 9;
@@ -493,6 +486,11 @@ jQuery(document).ready(function() {
   		if (jQuery('#idprod').val() > 0) jQuery('#dp_desc').focus();
 		if (jQuery('#idprodfournprice').val() > 0) jQuery('#dp_desc').focus();
 	});
+
+	<?php if (GETPOST('prod_entry_mode') == 'predef') { // When we submit with a predef product and it fails we must start with predef ?>
+		setforpredef();
+	<?php } ?>
+
 });
 
 /* Function to set fields from choice */
diff --git a/htdocs/fourn/commande/card.php b/htdocs/fourn/commande/card.php
index 7750250b00b..eefd5c961e2 100644
--- a/htdocs/fourn/commande/card.php
+++ b/htdocs/fourn/commande/card.php
@@ -251,7 +251,7 @@ if ($action == 'addline' && $user->rights->fournisseur->commande->creer)
     	$idprod=0;
     	$productsupplier = new ProductFournisseur($db);
 
-    	if (GETPOST('idprodfournprice') == -1 || GETPOST('idprodfournprice') == '') $idprod=-2;	// Same behaviour than with combolist. When not select idprodfournprice is now -2 (to avoid conflict with next action that may return -1)
+    	if (GETPOST('idprodfournprice') == -1 || GETPOST('idprodfournprice') == '') $idprod=-99;	// Same behaviour than with combolist. When not select idprodfournprice is now -99 (to avoid conflict with next action that may return -1, -2, ...)
 
     	if (GETPOST('idprodfournprice') > 0)
     	{
@@ -294,12 +294,12 @@ if ($action == 'addline' && $user->rights->fournisseur->commande->creer)
     			$date_end
     		);
     	}
-    	if ($idprod == -2 || $idprod == 0)
+    	if ($idprod == 0 || $idprod == -99)
     	{
     		// Product not selected
     		$error++;
     		$langs->load("errors");
-    		setEventMessage($langs->trans("ErrorFieldRequired",$langs->transnoentitiesnoconv("ProductOrService")), 'errors');
+    		setEventMessage($langs->trans("ErrorFieldRequired",$langs->transnoentitiesnoconv("ProductOrService")).' '.$langs->trans("or").' '.$langs->trans("NoPriceDefinedForThisSupplier"), 'errors');
     	}
     	if ($idprod == -1)
     	{
diff --git a/htdocs/product/class/product.class.php b/htdocs/product/class/product.class.php
index 653925701ad..ac3d8e967a2 100644
--- a/htdocs/product/class/product.class.php
+++ b/htdocs/product/class/product.class.php
@@ -1229,14 +1229,14 @@ class Product extends CommonObject
 				}
 				else
 				{
-					$this->error=$this->db->error();
+					$this->error=$this->db->lasterror();
 					return -3;
 				}
 			}
 		}
 		else
 		{
-			$this->error=$this->db->error();
+			$this->error=$this->db->lasterror();
 			return -2;
 		}
 	}