diff --git a/404.md b/404.md
index 8196fc9da3..bed3f06ec1 100644
--- a/404.md
+++ b/404.md
@@ -10,7 +10,7 @@ $( document ).ready(function() {
   var doRedirect=false;
   var forwardingURL=window.location.href;
   for (i=0;i<oldURLs.length;i++) {
-    if (window.location.href.indexOf(oldURLs[i]) > -1) {
+    if (window.location.href.indexOf(oldURLs[i])) > -1) {
       doRedirect=true;
       forwardingURL=forwardingURL.replace(oldURLs[i],"");
     }