diff --git a/cas.module b/cas.module
index 21d42ef..ec4ac53 100644
--- a/cas.module
+++ b/cas.module
@@ -179,7 +179,7 @@ function cas_login_check($force_authentication = TRUE) {
     $user = drupal_anonymous_user();
     // Only display error messages only if the user intended to log in.
     if ($force_authentication) {
-      drupal_set_message(t('No account found for %cas_name.', array('%cas_name' => $cas_name)));
+      drupal_set_message(t('No account found for %cas_name.', array('%cas_name' => $cas_name)), 'error');
     }
   }
 }