diff --git a/apps/files/admin.php b/apps/files/admin.php
index c183a4ba4b..76616bc437 100644
--- a/apps/files/admin.php
+++ b/apps/files/admin.php
@@ -35,7 +35,7 @@ $post_max_size = OCP\Util::computerFileSize(ini_get('post_max_size'));
 $post_max_size_possible = OCP\Util::computerFileSize(get_cfg_var('post_max_size'));
 $maxUploadFilesize = OCP\Util::humanFileSize(min($upload_max_filesize, $post_max_size));
 $maxUploadFilesizePossible = OCP\Util::humanFileSize(min($upload_max_filesize_possible, $post_max_size_possible));
-if($_POST && OC_Util::isCallRegistered) {
+if($_POST && OC_Util::isCallRegistered()) {
 	if(isset($_POST['maxUploadSize'])) {
 		if(($setMaxSize = OC_Files::setUploadLimit(OCP\Util::computerFileSize($_POST['maxUploadSize']))) !== false) {
 			$maxUploadFilesize = OCP\Util::humanFileSize($setMaxSize);