I am having the same issue.  I backed up my old phone (LGVX8560) with BA and then activated my new phone (LG-VN270) and when I installed BA and attempted to run it, received an invalid PIN message. I can still get into the BA data on line and confirm the PIN is as expenced. I can change the PIN from the new phone and it when I go to the Web, the PIN has indeed changed but I still get the invalid PIN message when I attempt a backup on the phone using the new PIN.