diff --git a/htdocs/product.class.php b/htdocs/product.class.php
index 389d2febaf2..e2568a7a3ae 100644
--- a/htdocs/product.class.php
+++ b/htdocs/product.class.php
@@ -1673,7 +1673,7 @@ class Product extends CommonObject
 	 *    \param      user        Utilisateur qui fait le lien
 	 *    \param      id_fourn    Id du fournisseur
 	 *    \param      ref_fourn   Reference chez le fournisseur
-	 *    \return     int         < 0 si erreur, > 0 si ok
+	 *    \return     int         < 0 if KO, 0 if link already exists, > 0 if OK
 	 */
 	function add_fournisseur($user, $id_fourn, $ref_fourn)
 	{
@@ -1737,8 +1737,9 @@ class Product extends CommonObject
 					$obj = $this->db->fetch_object($resql);
 					$this->product_fourn_id = $obj->rowid;
 				}
+			
+				return 0;
 			}
-			$this->db->free($resql);
 		}
 		else
 		{
diff --git a/htdocs/product/fournisseurs.php b/htdocs/product/fournisseurs.php
index f1c034c5f1b..b31772ffd23 100644
--- a/htdocs/product/fournisseurs.php
+++ b/htdocs/product/fournisseurs.php
@@ -115,7 +115,15 @@ if ($_POST["action"] == 'updateprice' && $_POST["cancel"] <> $langs->trans("Canc
 				$error++;
 				$mesg='<div class="error">'.$product->error.'</div>';
 			}
-
+			if ($ret == 0)
+			{
+				$error++;
+				$mesg='<div class="error">'.$langs->trans("ReferenceSupplierIsAlreadyAssociatedWithAProduct").'</div>';
+			}
+		}
+		
+		if (! $error)
+		{
 			if ($_POST["qty"])
 			{
 				if ($_POST["price"] >= 0)
@@ -124,22 +132,15 @@ if ($_POST["action"] == 'updateprice' && $_POST["cancel"] <> $langs->trans("Canc
 					$result=$supplier->fetch($_POST["id_fourn"]);
 
 					$ret=$product->update_buyprice($_POST["qty"], $_POST["price"], $user, $_POST["price_base_type"], $supplier);
-					if (!$error)
+					if ($ret < 0)
 					{
-						if ($ret < 0)
+						$error++;
+						$mesg='<div class="error">'.$product->error.'</div>';
+						if ($ret == -2)
 						{
-							$error++;
-							$mesg='<div class="error">'.$product->error.'</div>';
-							if ($ret == -2)
-							{
-								$mesg='<div class="error">'.$langs->trans("ProductHasAlreadyReferenceInThisSupplier").'</div>';
-							}
+							$mesg='<div class="error">'.$langs->trans("ProductHasAlreadyReferenceInThisSupplier").'</div>';
 						}
 					}
-					else
-					{
-						$mesg='<div class="error">'.$langs->trans("ReferenceSupplierIsAlreadyAssociatedWithAProduct").'</div>';
-					}
 				}
 				else
 				{