diff --git a/frontend-js/src/main/js/ServerConnector.js b/frontend-js/src/main/js/ServerConnector.js
index 2e4271142cb1255281a9a1a093667111457b2cd2..dd56cdb1f180788d70750940eb763d9b50ef5348 100644
--- a/frontend-js/src/main/js/ServerConnector.js
+++ b/frontend-js/src/main/js/ServerConnector.js
@@ -76,6 +76,12 @@ ServerConnector.getMaxOverlayColorInt = function() {
 
 ServerConnector.readFile = function(url, description) {
   var self = this;
+
+  if (self.getSessionData().getToken() === undefined) {
+    self.getSessionData().setLogin(undefined);
+    window.location.reload(false);
+  }
+
   if (description === undefined) {
     description = url;
   }