If you have Diagzone version 1 app, you won't be able to log in any more with old password. But if you go to the website diagzone.com, you can login manually from browser, and change the password. Then you can use new password to log in from the Diagzone app, but I warn you not to do it, because you won't be able to communicate with your dongle any more if you do any updates. Best keep it logged out, and it if works for your car, it works.
