Прикрепление файла к задаче

CModule::IncludeModule('tasks');

$storage = Bitrix\Disk\Driver::getInstance()->getStorageByUserId($USER_ID);
$folder = $storage->getFolderForUploadedFiles();
$arFile = CFile::MakeFileArray($FILE_ID);
$file = $folder->uploadFile($arFile, array(
   'NAME' => $arFile["name"],
   'CREATED_BY' => $USER_ID
), array(), true);
$FILE_ID = $file->getId();

$oTaskItem = new CTaskItem($taskId, $userId);
$rs = $oTaskItem->Update(array("UF_TASK_WEBDAV_FILES" => Array("n$FILE_ID")));