diff --git a/modules/purchaseguide/purchaseguide.php b/modules/purchaseguide/purchaseguide.php
index 8da5ae21..2d56c622 100644
--- a/modules/purchaseguide/purchaseguide.php
+++ b/modules/purchaseguide/purchaseguide.php
@@ -284,16 +284,22 @@ class PurchaseGuide extends Module
 	        $id_category = $postModel->id_guide_category;
 	    }
     
-	    // Get selected categories
-	    $model = new GuideCategory($id_category);
-        if ($model->id_parent === 0) {
-            $id_main_category = $id_category;
-            $id_child_category = 0;
-        } else {
-            $mainCategory = $model->getCategoryLang($model->id_parent, $cookie->id_lang);
-            $id_main_category = $mainCategory['id_guide_category'];
-            $id_child_category = $id_category;
-        }
+	    if($id_category == 0) {
+	        $model = new GuideCategory();
+	        $id_main_category = $id_child_category = 0;
+	    }
+	    else {
+	        // Get selected categories
+	        $model = new GuideCategory($id_category);
+	        if ($model->id_parent == 0) {
+	            $id_main_category = $id_category;
+	            $id_child_category = 0;
+	        } else {
+	            $mainCategory = $model->getCategoryLang($model->id_parent, $cookie->id_lang);
+	            $id_main_category = $mainCategory['id_guide_category'];
+	            $id_child_category = $id_category;
+	        }
+	    }
         $tree = $model->getTree($cookie->id_lang, $isEmployee);
         
         $smarty->assign(array(