On backup/moodle2/backup_custom_fields.php change fill_values function of file_nested_element class public function fill_values($values) { // Fill values parent::fill_values($values); // Do our own tasks (copy file from moodle to backup)   //ADD THIS! $bc = backup_ui::load_controller($backupid); if($bc && $bc->get_plan()->get_mode() != backup::MODE_IMPORT){ try { backup_file_manager::copy_file_moodle2backup($this->backupid, $values); } catch (file_exception $e) { $this->add_result(array('missing_files_in_pool' => true)); $this->add_log('missing file in pool: ' . $e->debuginfo, backup::LOG_WARNING); } } } On backup/util/dbops/restore_dbops.class.php on funcion send_files_to_pool change the contents inside "if (empty($file->repositoryid)) {" if (empty($file->repositoryid)) { // create the file in the filepool if it does not exist yet if (!$fs->file_exists($newcontextid, $component, $filearea, $rec->newitemid, $file->filepath, $file->filename)) { //ADD THIS if($copy_fileid = $DB->get_field('files','id',array('contenthash'=>$file->contenthash))){ $file_record = array( 'contextid' => $newcontextid, 'component' => $component, 'filearea' => $filearea, 'itemid' => $rec->newitemid, 'filepath' => $file->filepath, 'filename' => $file->filename, 'timecreated' => $file->timecreated, 'timemodified'=> $file->timemodified, 'userid' => $mappeduserid, 'author' => $file->author, 'license' => $file->license, 'sortorder' => $file->sortorder ); $fs->create_file_from_storedfile($file_record, $copy_fileid); } else { // this is a regular file, it must be present in the backup pool $backuppath = $basepath . backup_file_manager::get_backup_content_file_location($file->contenthash);   // The file is not found in the backup. if (!file_exists($backuppath)) { $result = new stdClass(); $result->code = 'file_missing_in_backup'; $result->message = sprintf('missing file %s%s in backup', $file->filepath, $file->filename); $result->level = backup::LOG_WARNING; $results[] = $result; continue; } $file_record = array( 'contextid' => $newcontextid, 'component' => $component, 'filearea' => $filearea, 'itemid' => $rec->newitemid, 'filepath' => $file->filepath, 'filename' => $file->filename, 'timecreated' => $file->timecreated, 'timemodified'=> $file->timemodified, 'userid' => $mappeduserid, 'author' => $file->author, 'license' => $file->license, 'sortorder' => $file->sortorder ); $fs->create_file_from_pathname($file_record, $backuppath); } }