diff --git a/www/common/cryptpad-common.js b/www/common/cryptpad-common.js
index 0c68d425c..1576275c7 100644
--- a/www/common/cryptpad-common.js
+++ b/www/common/cryptpad-common.js
@@ -246,7 +246,7 @@ define([
     var getUserHash = common.getUserHash = function () {
         var hash = localStorage[userHashKey];
 
-        if (hash) {
+        if (hash && ['undefined', 'undefined/'].indexOf(hash) !== -1) {
             var sHash = common.serializeHash(hash);
             if (sHash !== hash) { localStorage[userHashKey] = sHash; }
         }