diff --git a/core/lib/Drupal/Core/FileTransfer/Form/FileTransferAuthorizeForm.php b/core/lib/Drupal/Core/FileTransfer/Form/FileTransferAuthorizeForm.php
index 6d70afc..061f169 100644
--- a/core/lib/Drupal/Core/FileTransfer/Form/FileTransferAuthorizeForm.php
+++ b/core/lib/Drupal/Core/FileTransfer/Form/FileTransferAuthorizeForm.php
@@ -156,7 +156,7 @@ public function validateForm(array &$form, array &$form_state) {
       catch (\Exception $e) {
         // The format of this error message is similar to that used on the
         // database connection form in the installer.
-        form_set_error('connection_settings', $form_state, $this->t('Failed to connect to the server. The server reports the following message: !message For more help installing or updating code on your server, see the <a href="@handbook_url">handbook</a>.', array(
+        $this->setFormError('connection_settings', $form_state, $this->t('Failed to connect to the server. The server reports the following message: !message For more help installing or updating code on your server, see the <a href="@handbook_url">handbook</a>.', array(
           '!message' => '<p class="error">' . $e->getMessage()  . '</p>',
           '@handbook_url' => 'http://drupal.org/documentation/install/modules-themes',
         )));