ATT.net required a password reset. At the next login it would not use the new password. ATT then sent me a secure message key to my phone. This allowed the reset, but then after exiting ATT and Firefox, the next time in the new password would not work, and my ATT account locked up with "too many tries". This took me about eight service calls to find the problem. It turns out that during a secure password reset, ATT generated a new file in Firefox's password list that had their new password name with a BLANK name for the users email address. So now Firefox was showing TWO PASSWORD FILES and ATT's login locked up. I was able to fix it within Firefox by entering my email address in the password file's blank name entry, and deleting the old Firefox entry by hand. Nowhere did either ATT or Firefox detect this condition.