diff --git a/tooling/scripts/win-zip.js b/tooling/scripts/win-zip.js
index 8455a54..ee32c7a 100644
--- a/tooling/scripts/win-zip.js
+++ b/tooling/scripts/win-zip.js
@@ -23,11 +23,12 @@
 var objShell = new ActiveXObject("shell.application");
 var zipFolder = objShell.NameSpace(zipPath);
 var sourceItems = objShell.NameSpace(sourcePath).items();
-if (zipFolder != null)
-{
+if (zipFolder != null) {
     zipFolder.CopyHere(sourceItems, 4|20);
-    WScript.Sleep(1000);
+    while (zipFolder.items().Count < sourceItems.Count) {
+        WScript.Sleep(100);
+    }
 }
 else {
-	WScript.Echo("Failed to create .zip file.");
+	WScript.StdErr.WriteLine("Failed to create .zip file.");
 }
\ No newline at end of file