If you have login issues, uninstall the application, and when you're asked, remove the data associated with the client. This is called a fresh installation. Firstly, make sure that the new password is changed and working. Log-in on the website. Secondly, re-download the client from its page and install it, then click on the Login button in the upper-left section of the main window. I have repeated this process, and it works normally without errors.