diff --git a/mod/assign/submission/file/locallib.php b/mod/assign/submission/file/locallib.php
index 1ac40d76f8a..d96b293009a 100644
--- a/mod/assign/submission/file/locallib.php
+++ b/mod/assign/submission/file/locallib.php
@@ -71,8 +71,9 @@ class assign_submission_file extends assign_submission_plugin {
 
         $defaultmaxfilesubmissions = $this->get_config('maxfilesubmissions');
         $defaultmaxsubmissionsizebytes = $this->get_config('maxsubmissionsizebytes');
-        $defaultfiletypes = $this->get_config('filetypeslist');
-        if ($defaultfiletypes === false) {
+        if ($this->assignment->has_instance()) {
+            $defaultfiletypes = $this->get_config('filetypeslist');
+        } else {
             $defaultfiletypes = get_config('assignsubmission_file', 'filetypes');
         }
         $defaultfiletypes = (string)$defaultfiletypes;