diff --git a/web/documentserver-example/nodejs/public/javascripts/jscript.js b/web/documentserver-example/nodejs/public/javascripts/jscript.js
index 212c3618..15f62b34 100644
--- a/web/documentserver-example/nodejs/public/javascripts/jscript.js
+++ b/web/documentserver-example/nodejs/public/javascripts/jscript.js
@@ -101,7 +101,8 @@ if (typeof jQuery != "undefined") {
     });
     
     var timer = null;
-    var checkConvert = function (filePass = null) {
+    var checkConvert = function (filePass) {
+        filePass = null;
         if (timer != null) {
             clearTimeout(timer);
         }