I have a couple of computers and an ipad that I use for operation of my 6400. mostly just use one computer, but now and then try the ipad. these two I have been able to log into Smart Link. On the other computer and another that I have SSDR loaded on when I try to log into Smart Link the login window comes up and the indicator spines for a few seconds and stops, but the screen is blank and of course no login place on the page. The only option is cancel on top bar. Is there a limit to a number of login devices. Totally lost on this.